is primarily a role-playing game for the PlayStation. The game was then adapted into a manga

Manga

Manga is the Japanese word for "comics" and consists of comics and print cartoons . In the West, the term "manga" has been appropriated to refer specifically to comics created in Japan, or by Japanese authors, in the Japanese language and conforming to the style developed in Japan in the late 19th...

 series written by and drawn by Keiji Gotoh

Keiji Gotoh

is a Japanese anime director, character designer, manga artist, and member of three man production team gímik whose works include Kiddy Grade and Uta Kata.- Television :* Thundercats , In-between animation...

 and an anime

Anime

is the Japanese abbreviated pronunciation of "animation". The definition sometimes changes depending on the context. In English-speaking countries, the term most commonly refers to Japanese animated cartoons....

 series produced by Gonzo, and first aired on April 3, 2000..

A six episode original video animation

Original video animation

, abbreviated as media , are animated films and series made specially for release in home-video formats. The term originated in relation to Japanese animation...

 (OVA) sequel, Gate Keepers 21

Gate Keepers 21

is a Japanese six-part sequel OVA series to the Gate Keepers animated TV series and has a darker and more serious plot than its predecessor. Some of the questions left unanswered in the TV series are answered in this sequel...

, was released in 2002. The main characters in the OVA sequel were the next generation of Gate Keepers.

All incarnations of the titled Gate Keepers series, follow the same basic premise and share most of their characters, with some major discrepancies (mainly involving the character Reiji Kageyama). A character from the game, Francine Allumage is completely absent from the anime. Another character from the game Misao Sakamori, was replaced in the anime with the new original character Megumi Kurogane (though Misao does make a guest appearance towards the end of the anime).

Plot

The story is set in 1969, a period of time in which Japan is experiencing intense economic and social development after the end of World War II

World War II

World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

 in 1945. Unbeknownst to humans, alien

Extraterrestrial life in popular culture

In popular cultures, "extraterrestrials" are life forms — especially intelligent life forms— that are of extraterrestrial origin .-Historical ideas:-Pre-modern:...

/interdimensional beings have emerged with plans to take over the world by sending numerous agents to wreak havoc in cities, turning people into robotic minions. They are referred to as .

In an attempt to confront the Invaders and defend the planet; an elite

Elite

Elite refers to an exceptional or privileged group that wields considerable power within its sphere of influence...

 but highly secret organization of peace-keepers called the Alien Exterminating Global Intercept System (more commonly known as A.E.G.I.S.), was set up with special funding from the government. They rely on the ability of "Gate Keepers", who have the power to open dimensional "gates" of a paranormal

Paranormal

Paranormal is a general term that designates experiences that lie outside "the range of normal experience or scientific explanation" or that indicates phenomena understood to be outside of science's current ability to explain or measure...

 energy that give them their superpowers

Superpower (ability)

Superpower is a popular culture term for a fictional superhuman ability. When a character possesses multiple such abilities, the terms super powers or simply powers are used...

. These superpowers are the only weapons that have any effect on Invaders.

Although A.E.G.I.S. has branches around the world, the series focuses on the Far East division in Japan. The headquarters of the Far East branch of A.E.G.I.S. lies beneath Tategami High School, a facade created by the organization to mask the active recruitment of new Gate Keepers. Since many of the candidates were High School students, the location allowed the agents to be enrolled in school and be available for a mission at a moment's notice.

A.E.G.I.S. members

Names with asterisks indicates an anime-only character.

Shun Ukiya, the focus of the series, is a young Japanese schoolboy (who permanently wears a bandage over his nose, the only exception being his appearance in the final chapter of Gatekeepers 21) with a deep passion for kendo

Kendo

, meaning "Way of The Sword", is a modern Japanese martial art of sword-fighting based on traditional Japanese swordsmanship, or kenjutsu.Kendo is a physically and mentally challenging activity that combines strong martial arts values with sport-like physical elements.-Practitioners:Practitioners...

. Ukiya discovers that he has the ability to open the Gate of Gales in a chance encounter with an Invader attack near his hometown, where he meets fellow Gate Keeper and childhood friend, Ruriko Ikusawa. He is subsequently invited to join A.E.G.I.S. after discovering the existence of Invaders and of A.E.G.I.S. Skills he developed after discovering his Gate includes 'Urotora Senpuu Kiri (Ultra Whirlwind Slash)' and 'Shinkuu Misairu (Vacuum Missile)'. His Gate is considered to be among the most powerful Gates to have been discovered. He inherited the Gate from his father, and, as disclosed in Gate Keepers 21

Gate Keepers 21

is a Japanese six-part sequel OVA series to the Gate Keepers animated TV series and has a darker and more serious plot than its predecessor. Some of the questions left unanswered in the TV series are answered in this sequel...

his daughter Ayane Isuzu inherited it in turn, although she avoids using it. His Gate color is blue.

Ruriko is one of the first Gate Keepers recruited in Japan by A.E.G.I.S. and controls the Gate of Life. Ruriko is the unhappy bearer of the nickname

Nickname

A nickname is "a usually familiar or humorous but sometimes pointed or cruel name given to a person or place, as a supposedly appropriate replacement for or addition to the proper name.", or a name similar in origin and pronunciation from the original name....

 'Rurippe' , which holds no real meaning except that Ukiya relates it to her childhood appearance as a sniveler (or one who always has a runny nose

Rhinorrhea

Rhinorrhea or rhinorrhoea is a condition where the nasal cavity is filled with a significant amount of mucous fluid. The condition, commonly known as "runny nose", occurs relatively frequently and is not usually considered dangerous. Rhinorrhea is a common symptom of allergies or certain diseases,...

). Viewed as a model student and an active participant in school activities, Ruriko only snaps when Ukiya uses her nickname in public. Her original ability involves a healing light and she utilizes it for combat through the materialization

Materialization

Materialization is the name of several things:*Materialization — a concept, in parapsychology, is the creation or appearance of matter from unknown sources....

 of a bow and arrow. She is taken by Reiji Kageyama and is convinced to hate others, thus changing her Gate into the Minus Gate of Genocide (a gate, according to Misao Sakimori, that should never be opened because of the devastation it brings). When she discovers that her secret love for Ukiya is reciprocated, her hatred fades and restores her Gate of Life. Her Gate color is yellow.

Despite the fact that Reiko is an extremely forgetful and absent-minded girl (perhaps a result of the shock from the divorce of her parents), she is an extremely talented pianist

Pianist

A pianist is a musician who plays the piano. A professional pianist can perform solo pieces, play with an ensemble or orchestra, or accompany one or more singers, solo instrumentalists, or other performers.-Choice of genres:...

 who discovered her Gate of Illusion when Invaders attacked her during her very first public recital

Recital

A recital is a musical performance. It can highlight a single performer, sometimes accompanied by piano, or a performance of the works of a single composer.The invention of the solo piano recital has been attributed to Franz Liszt....

 at a theater. Her ability to create illusions while playing music does not go unnoticed by Invaders, who suffer intense agony when they hear her melodies. She is the only Gate Keeper other than Shun Ukiya who has operated the prototype Unit 00 Gate Robo, and the only one to pilot a jet aircraft

Jet aircraft

A jet aircraft is an aircraft propelled by jet engines. Jet aircraft generally fly much faster than propeller-powered aircraft and at higher altitudes – as high as . At these altitudes, jet engines achieve maximum efficiency over long distances. The engines in propeller-powered aircraft...

. But, individually, she utilizes any keyboard musical instrument as a weapon (like a melodica

Melodica

The melodica, also known as the "blow-organ" or "key-flute", is a free-reed instrument similar to the melodeon and harmonica. It has a musical keyboard on top, and is played by blowing air through a mouthpiece that fits into a hole in the side of the instrument. Pressing a key opens a hole,...

). In the final episodes, after seeing one of her comrades getting hit, she snapped, unleashing the full force of her Gate's powers. Her Gate color is pink.

A tomboy

Tomboy

A tomboy is a girl who exhibits characteristics or behaviors considered typical of the gender role of a boy, including the wearing of typically masculine-oriented clothes and engaging in games and activities that are often physical in nature, and which are considered in many cultures to be the...

ish athlete, Kaoru was tormented by her previous stint in the track team. She awoke her own Gate of Close Combat, which increases her natural physical abilities to insane proportions, to create such a logic defying world record for sprinting that it was revoked. She jumped at the chance to join A.E.G.I.S. so that she could use her abilities without restraint, and to 'steal Ukiya from Ruriko'. She wears her PE

Physical education

Physical education or gymnastics is a course taken during primary and secondary education that encourages psychomotor learning in a play or movement exploration setting....

 uniform; a white shirt with her class tag and blue burūmā

Bloomers (clothing)

Bloomers is a word which has been applied to several types of divided women's garments for the lower body at various times.-Fashion bloomers :...

, when fighting Invaders. Her skills include 'Kaoru Punch' and 'Kaoru Kick', among other self-named close combat fighting styles, and her incredible lifting and stopping abilities (like her Hustle move, where she lifts heavy objects and turns them into projectiles) Her Gate color is blue, like Shun's.

A small German-Japanese girl from A.E.G.I.S. Germany who maintains the Gate of Perception. She resembles Megumi Kurogane in some aspects but their personalities are totally different. She operates Gate Robo Unit 03. In the game she plays a bigger role and is one of the first characters to join the player. In the game Misao controls the Gate of Wall. Her role was replaced by Megumi in the anime who is an anime only character. In the anime, her Gate of Perception gives her powerful and accurate precognitive abilities. Her Gate color is green.

*

This mumbling asocial girl has the ability to set up force fields around herself with her Gate of Walls (Gate of Steel in other translations). Megumi has a secret loathing for Ruriko — she is bitterly jealous of Ruriko's wealth, intelligence and popularity (which contrasts with her own state of living, being a delivery girl for a noodle

Noodle

The noodle is a type of food, made from any of a variety of doughs, formed into long thin ribbons, strips, curly-cues, waves, helices, pipes, tubes, strings, or other various shapes, sometimes folded. They are usually cooked in a mixture of boiling water and/or oil. Depending upon the type, noodles...

 shop) and hates it when Ruriko outshines her without seeming to put forth any effort. She is a member of A.E.G.I.S. but does not appear to be particularly interested in socializing with her fellow Gate Keepers. She eventually joins Reiji and the Invaders when Reiji promises to 'recognize her true abilities.' She gains a Minus Gate, the Gate of Invasion (which allows her to invade into the minds of others), but Reiji betrays her when Ruriko becomes good again. Megumi replaces the role of Misao from the game though it should be noted whilst both characters share the same gate they both have very different personalities. Her Gate color is green.

Wielder of the Gate of Fire, Fei hails from the Chinese (Shanghai) branch of A.E.G.I.S., and joined the Japanese branch to help out with the high concentration of Invader activity. Her companion, a golden monkey called Ukiya (a licensed A.E.G.I.S. agent—but was once confused with Shun Ukiya), often helps her target Red Invaders. Her skills include 'Da Xiong Mao' (Exploding Panda Fireball) and a fiery dragon (Shocking Fire Dragon). According to a flashback

Flashback (narrative)

Flashback is an interjected scene that takes the narrative back in time from the current point the story has reached. Flashbacks are often used to recount events that happened before the story’s primary sequence of events or to fill in crucial backstory...

, her brother and grandfather were taken away from their house in China by unidentified men (possibly a reference to the Cultural Revolution

Cultural Revolution

The Great Proletarian Cultural Revolution, commonly known as the Cultural Revolution , was a socio-political movement that took place in the People's Republic of China from 1966 through 1976...

), never to be seen again. Her Gate color is red.

A fashion model from the United States of America who is affiliated with A.E.G.I.S. (in the game she actually joins the A.E.G.I.S. branch quite early on as she has been transferred there from the American branch). She controls the Gate of Lightning and is the operator of Gate Robo Unit 02. She plays a bigger role in the game and has a lot more character development since she is one of the main characters. Her Gate color is violet.

Francine only appears in the game and manga. She controls the Gate of Heat and Explosion (Fei actually uses this gate in the anime whereas in the game Fei's gate was the Gate of a Hundred Animals). Francine was originally assigned to the French branch since she is French. She is later assigned to the A.E.G.I.S. branch. Despite being French in origin, she is actually a western film lover and speaks fluent English. In her game image song she mentions two of the most famous western film stars (John Wayne

John Wayne

Marion Mitchell Morrison , better known by his stage name John Wayne, was an American film actor, director and producer. He epitomized rugged masculinity and became an enduring American icon. He is famous for his distinctive calm voice, walk, and height...

 and Clint Eastwood

Clint Eastwood

Clinton "Clint" Eastwood, Jr. is an American film actor, director, producer, composer and politician. Eastwood first came to prominence as a supporting cast member in the TV series Rawhide...

). Although she likes America she has never actually been there despite the fact that she usually cracks American jokes. She is a cheerful, fun-loving girl whose goal in life is to make 1000 friends.

She is the oldest Gate Keeper in Japan, having been born in 1169. However, she has stopped aging and appears in 1969 as a young girl in a white kimono

Kimono

The is a Japanese traditional garment worn by men, women and children. The word "kimono", which literally means a "thing to wear" , has come to denote these full-length robes...

 (and again in Gate Keepers 21

Gate Keepers 21

is a Japanese six-part sequel OVA series to the Gate Keepers animated TV series and has a darker and more serious plot than its predecessor. Some of the questions left unanswered in the TV series are answered in this sequel...

 without any trace of aging). Like her name Yukino suggests, she commands the Gate of Ice and Snow, being able to summon blizzard

Blizzard

A blizzard is a severe snowstorm characterized by strong winds. By definition, the difference between blizzard and a snowstorm is the strength of the wind. To be a blizzard, a snow storm must have winds in excess of with blowing or drifting snow which reduces visibility to 400 meters or ¼ mile or...

s and hail

Hail

Hail is a form of solid precipitation. It consists of balls or irregular lumps of ice, each of which is referred to as a hail stone. Hail stones on Earth consist mostly of water ice and measure between and in diameter, with the larger stones coming from severe thunderstorms...

. She is one of the most powerful Gate Keepers in the series, being referred to as a 'top-secret, High-Level Gate Keeper A.E.G.I.S. has been hiding' by Reiji Kageyama. One of her unique traits is the fact that she converses in Tanka poetry. She does help the A.E.G.I.S. members, despite being not an official member of A.E.G.I.S. She also has her pet ermine

Ermine

Ermine has several uses:* A common name for the stoat * The white fur and black tail end of this animal, which is historically worn by and associated with royalty and high officials...

 Hisame with her. She returns in Gate Keepers 21

Gate Keepers 21

is a Japanese six-part sequel OVA series to the Gate Keepers animated TV series and has a darker and more serious plot than its predecessor. Some of the questions left unanswered in the TV series are answered in this sequel...

. In the game Yukino is actually a hidden character, but if she joins, she interacts more with the main characters and actually attends the same school as them (she joins the same class Fei is in) unlike the anime where she usually keeps her distance from the rest of the characters. Her Gate color is white.

(a.k.a Bancho or Big Boss)*

The over-enthusiastic Osaka

Osaka

is a city in the Kansai region of Japan's main island of Honshu, a designated city under the Local Autonomy Law, the capital city of Osaka Prefecture and also the biggest part of Keihanshin area, which is represented by three major cities of Japan, Kyoto, Osaka and Kobe...

n gangster-turned-good, Bancho was recruited into the team only because Ukiya believed Bancho 'has the eyes of a Gate Keeper'. With the mindset of a samurai

Samurai

is the term for the military nobility of pre-industrial Japan. According to translator William Scott Wilson: "In Chinese, the character 侍 was originally a verb meaning to wait upon or accompany a person in the upper ranks of society, and this is also true of the original term in Japanese, saburau...

, Bancho likens the girls in the Gate Keepers team as princesses and himself as their hero. It is only much, much later in the series that he reveals his latent Gate Keeper ability, the Gate of Solid Crush, which seemingly attracts Kaoru (perhaps because of the similarity of their gates). His Gate color is orange.

Voice actor

Seiyu

Voice acting in Japan has far greater prominence than in most other countries. Japan's large animation industry produces 60% of the animated series in the world; as a result, Japanese voice actors, or , are able to achieve fame on a national and international level.Besides acting as narrators and...

 Koyasu also appeared as himself in one of the later episodes.

The head of the mechanics

Mechanics

Mechanics is the branch of physics concerned with the behavior of physical bodies when subjected to forces or displacements, and the subsequent effects of the bodies on their environment....

 department of AEGIS. Megane, as he is fondly called, is a genius kid who can easily repair machines. In both the game and anime he helps the Gate Keepers by bringing the Gate Engine or Gate Robo to them, even restoring an out-of-commission Gate Robo (after the battle at the Tokyo Tower

Tokyo Tower

is a communications and observation tower located in Shiba Park, Minato, Tokyo, Japan. At , it is the second tallest artificial structure in Japan. The structure is an Eiffel Tower-inspired lattice tower that is painted white and international orange to comply with air safety regulations.Built in...

). In the anime he is good friends with Bancho who often helps Megane with the mechanics. "Megane" is Japanese for spectacles or glasses and is a common nickname for kids who wear glasses in Japan; he is called Specs in the English version.

Voice actor Kozakura also appeared as herself in one of the later episodes.

/

The Commander of the A.E.G.I.S. Far-East Branch oversees the operations and deployments of Japan's Gate Keepers. He was an Ensign

Ensign (rank)

Ensign is a junior rank of a commissioned officer in the armed forces of some countries, normally in the infantry or navy. As the junior officer in an infantry regiment was traditionally the carrier of the ensign flag, the rank itself acquired the name....

 in the Imperial Japanese Navy

Imperial Japanese Navy

The Imperial Japanese Navy was the navy of the Empire of Japan from 1869 until 1947, when it was dissolved following Japan's constitutional renunciation of the use of force as a means of settling international disputes...

 during World War II, and was supposed to fly an Ohka

Ohka

The Yokosuka MXY-7 Ohka was a purpose-built, rocket powered human-guided anti-shipping kamikaze attack plane employed by Japan towards the end of World War II...

 piloted bomb on a suicide mission in 1945, near the end of World War II. However, his mothership was shot down, and ironically, he was the sole survivor. When he attempted to commit suicide

Suicide

Suicide is the act of intentionally causing one's own death. Suicide is often committed out of despair or attributed to some underlying mental disorder, such as depression, bipolar disorder, schizophrenia, alcoholism, or drug abuse...

 with a pistol

Nambu pistol

was a semi-automatic pistol used by the Imperial Japanese Army and Navy during the First and Second World Wars. The pistol had two variants, the Type A , and the Type 14 .-History:...

 after being rescued by the US Navy, he was restrained by a sailor who told him two words: "Stay alive." This changed his life and after the war he was one of the first members of the Police Reserve (later the Japan Self Defense Force). In the PlayStation Gate Keepers RPG and the Gate Keepers 1985 novel, it is revealed that the Commander's name is and he has the Gate of Time and Space.

The private secretary to the Commander (Shirei) and is practically Second-in-Command of A.E.G.I.S. Far East (in Shirei's absence). She is also the school nurse at Tategami High School. She hates violence and acts as an adviser to the Gate Keepers (both at school and when they perform their Gate Keeper duties). Despite her feelings for the Commander, she was briefly engaged (an arranged marriage) to a man who was revealed to be an Invader.

*

A British racer who drives a Lotus

Lotus Cars

Lotus Cars is a British manufacturer of sports and racing cars based at the former site of RAF Hethel, a World War II airfield in Norfolk. The company designs and builds race and production automobiles of light weight and fine handling characteristics...

 Seven (Caterham Seven

Caterham Seven

The Caterham Seven is a super-lightweight sports car produced by Caterham Cars in the United Kingdom. It is based on the Lotus Seven, a lightweight sports car sold in kit and factory-built form by Lotus Cars, from the late 1950s to the early 1970s...

) and is a member of A.E.G.I.S. England sent to Japan by A.E.G.I.S. HQ. He controls the Gate of Supersonic, and is uses it in conjunction with Gate Robo Unit 01. Overconfident after beating the top brass of the Invaders in their first encounter on Dream Island, he got himself killed by one accurate blast from Kikai Shogun's tank in a rematch. Luckily Ruriko was just around and revived him. His Gate color is blue.

Invaders

At a young age by many tragedies in his family, his original Gate of Foresight was warped into the Jet-Black Gate of Darkness. The Gate of Darkness allows him to do many things unavailable to the other Gate Keepers. For example, he is able to transport objects, change his outfit and perform a variety of attacks. He possesses clairvoyance

Clairvoyance

The term clairvoyance is used to refer to the ability to gain information about an object, person, location or physical event through means other than the known human senses, a form of extra-sensory perception...

, which the Commander theorizes helped him open his gate initially by allowing him to 'Grasp a future beyond his reach'. A formidable enemy, Kageyama's secret identity is not discovered until it was too late, even though he had been befriended by Ukiya as a student of Tategami High School. In the anime, his real name is revealed to be , the son of a rich man who was duped by one of his associates. He returns in Gate Keepers 21

Gate Keepers 21

is a Japanese six-part sequel OVA series to the Gate Keepers animated TV series and has a darker and more serious plot than its predecessor. Some of the questions left unanswered in the TV series are answered in this sequel...

 as a middle-aged businessman working for A.E.G.I.S. Network, and is seen riding a blue TVR Tuscan

TVR Tuscan

-Engine:Five different inline six engine options were offered to customers. Four of these were variants of the 4.0 L Speed Six making different amounts of power and torque, depending on the trim level selected...

. He is missing several body parts such as his arm, leg, and internal organs due to the overuse of his Gate.

The evil Count

Count

A count or countess is an aristocratic nobleman in European countries. The word count came into English from the French comte, itself from Latin comes—in its accusative comitem—meaning "companion", and later "companion of the emperor, delegate of the emperor". The adjective form of the word is...

 is a top ranking Invader who manipulates the minds of people into believing false ideas and twisting their hearts to suit the needs of the Invaders. He once even had the Gate Keepers in his trap. He returns in Gate Keepers 21 to battle his archenemy's daughter, only to be defeated. His name is also known as Baron Akuma in the English anime.

This Hitler-like character with a deep, raspy voice and a "Heil Vader!" catchphrase is a top Invader with the power to control machinery. He was said to have caused the disappearance of the SS Marine Sulphur Queen

SS Marine Sulphur Queen

SS Marine Sulphur Queen, T2 tanker ship converted to carrying molten sulphur, noted for its disappearance in 1963 near the southern coast of Florida, taking the lives of 39 crewmen....

 in the Bermuda Triangle

Bermuda Triangle

The Bermuda Triangle, also known as the Devil's Triangle, is a region in the western part of the North Atlantic Ocean where a number of aircraft and surface vessels allegedly disappeared under mysterious circumstances....

 and made it resurface 6 years later standing up in Yokohama Bay. He first appears trying to control the first Shinkansen

Shinkansen

The , also known as THE BULLET TRAIN, is a network of high-speed railway lines in Japan operated by four Japan Railways Group companies. Starting with the Tōkaidō Shinkansen in 1964, the network has expanded to currently consist of of lines with maximum speeds of , of Mini-shinkansen with a...

 and sends it on a destructive maiden journey

Maiden voyage

The maiden voyage of a ship, aircraft or other craft is the first journey made by the craft after shakedown. A number of traditions and superstitions are associated with it....

. He also returns in Gate Keepers 21

Gate Keepers 21

is a Japanese six-part sequel OVA series to the Gate Keepers animated TV series and has a darker and more serious plot than its predecessor. Some of the questions left unanswered in the TV series are answered in this sequel...

 only to be defeated by the daughter of the man who defeated him, with the gate engine.

He was a teacher at Tategami High, and is Megumi Kurogane's favorite teacher. But he is hated by most of the students. He is a red Invader with fake identity papers and armed with a chalk-shooting gun. It was slain by Shun Ukiya right in front of Megumi.

Ochiai-kun's Fiance, he's obnoxious and loudmouthed, therefore making him a perfect candidate for an Invader.

The fiance of Ochiai's high school classmate who chased her and Shirei after knowing they know his true identity. Being a race driver, he has an unusual obsession to become Number One. He drove a Nissan Skyline GT-R

Nissan Skyline GT-R

The Nissan Skyline GT-R is a Japanese sports car based on the Nissan Skyline range.The first GT-Rs were produced from 1969–1973. After a 16 year hiatus since the KPGC110 in 1972, the GT-R name was revived in 1989 with the Skyline R32. This car was nicknamed "Godzilla" by the Australian motoring...

 KPGC10 "Hakosuka."

Others

*

Shun's younger sister. She supports her big brother on his activities with the AEGIS. She has a crush on a boy named Hideki Ikeda. She also appears in Gate Keepers 21 as Ayame's aunt. Only appears in the anime.

Forms and disguises

Invader Soldier

The Invader soldier unit usually resembles a humanoid robot

Humanoid robot

A humanoid robot or an anthropomorphic robot is a robot with its overall appearance, based on that of the human body, allowing interaction with made-for-human tools or environments. In general humanoid robots have a torso with a head, two arms and two legs, although some forms of humanoid robots...

 in black suit, hat, dark glasses and holding a suitcase. Combined together in Fusion Mode, they create the more powerful and larger versions of Invaders of which can take multiple forms like centipede

Centipede

Centipedes are arthropods belonging to the class Chilopoda of the subphylum Myriapoda. They are elongated metameric animals with one pair of legs per body segment. Despite the name, centipedes can have a varying number of legs from under 20 to over 300. Centipedes have an odd number of pairs of...

s, balls, and fake highways. Their weakness is the Red Invader, who initiates the Fusion and if destroyed, will cause a similar chain reaction to the other Invaders in the same form. The Invaders are not human but they can take on the appearance of a human in the original series.

Cyclopean Dog

An Invader that was disguised as an irritable Japanese Spitz

Japanese Spitz

The is a small to medium breed of dog of the Spitz type. The Japanese Spitz is a companion dog and pet. There are varying standards around the world as to the ideal size of the breed, but they are always larger than their smaller cousins, the Pomeranian. They were developed in Japan in the 1920s...

. Feng Fei Ling initially thought that its keeper, a vendor of stone-roasted yams, was the Invader, but it revealed itself after being confronted by Shun and the other Gatekeepers.

Six-Engined Jumbo Jet

One of the many forms of the Invaders taking the form of a six-engined jumbo jet. It turned into a dinosaur

Dinosaur

Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...

 then into a Concorde

Concorde

Aérospatiale-BAC Concorde was a turbojet-powered supersonic passenger airliner, a supersonic transport . It was a product of an Anglo-French government treaty, combining the manufacturing efforts of Aérospatiale and the British Aircraft Corporation...

 when Shun Ukiya shot one of its engines and crashed. It was finally put out of commission by Fei Fen Ring with the help of the Gate Engine.

ET-11 Ball-Type Invader

This conglomeration of Invaders first appeared in the first episode, attacking the A.E.G.I.S. bus carrying the Gate Engine. Its core is the red Invader. According to A.E.G.I.S. archives, it first appeared in Los Angeles.

ET-13 Drill-Type Invader

Also made an appearance as a dam

Dam

A dam is a barrier that impounds water or underground streams. Dams generally serve the primary purpose of retaining water, while other structures such as floodgates or levees are used to manage or prevent water flow into specific land regions. Hydropower and pumped-storage hydroelectricity are...

 buster in Germany, this one wreaked havoc in a shopping mall in Shibuya

Shibuya, Tokyo

is one of the 23 special wards of Tokyo, Japan. As of 2008, it has an estimated population of 208,371 and a population density of 13,540 persons per km². The total area is 15.11 km²....

.

Twin-Barreled Tank

Also appearing in Europe, this one is commandeered by Kaiser Kikai himself and merged with a junked battleship

Battleship

A battleship is a large armored warship with a main battery consisting of heavy caliber guns. Battleships were larger, better armed and armored than cruisers and destroyers. As the largest armed ships in a fleet, battleships were used to attain command of the sea and represented the apex of a...

 on Dream Island. With the tank, Kaiser Kikai was able to defeat the combined (and over-confident) forces of Gate Robo Units 1-3, seriously injuring Jim Skylark in the process.

"Chef Boyardee

Chef Boyardee

Chef Boyardee is a brand of canned pasta products sold internationally by ConAgra Foods. Named after its founder, Italian-American immigrant Ettore Boiardi, the company began production in the United States in the 1920s...

"-style Invader

A cross between a giant billboard

Billboard (advertising)

A billboard is a large outdoor advertising structure , typically found in high traffic areas such as alongside busy roads. Billboards present large advertisements to passing pedestrians and drivers...

 and a building. Made its appearance at the start of the "Sally Forth, Gate-Robo!" episode, which Reiko Asagiri accidentally revived with her Maiden's Prayer.

Highway-Type Invader

Disguised itself as part of the Tomei Highway, allowing it to strike unexpectedly and flatten any car in the highway, only to vanish and go undetected. This was the first invader Kaoru Konoe has ever encountered.

A.E.G.I.S. weapons, transport and gear

Gate Engine

The Gate Engine is a device that is able to amplify

Amplifier

Generally, an amplifier or simply amp, is a device for increasing the power of a signal.In popular use, the term usually describes an electronic amplifier, in which the input "signal" is usually a voltage or a current. In audio applications, amplifiers drive the loudspeakers used in PA systems to...

 the abilities of a Gate Keeper. However; due to its size, it requires support personnel to transport it to and from the battlefield. Using this device, Konoe Kaoru was able to stop a runaway Shinkansen

Shinkansen

The , also known as THE BULLET TRAIN, is a network of high-speed railway lines in Japan operated by four Japan Railways Group companies. Starting with the Tōkaidō Shinkansen in 1964, the network has expanded to currently consist of of lines with maximum speeds of , of Mini-shinkansen with a...

 a la Superman

Superman

Superman is a fictional comic book superhero appearing in publications by DC Comics, widely considered to be an American cultural icon. Created by American writer Jerry Siegel and Canadian-born American artist Joe Shuster in 1932 while both were living in Cleveland, Ohio, and sold to Detective...

, and Fei Fen Ring was able to down the Concorde

Concorde

Aérospatiale-BAC Concorde was a turbojet-powered supersonic passenger airliner, a supersonic transport . It was a product of an Anglo-French government treaty, combining the manufacturing efforts of Aérospatiale and the British Aircraft Corporation...

-shaped Invader. It was shrunk to fit inside the Gate Robo--whose design was invented by Shun's father.

Gate Robo

A mecha

Mecha

A mech , is a science fiction term for a large walking bipedal tank or robot, including ones on treads and animal shapes.-Characteristics:...

 that uses a more compact version of the Gate Engine as its power source. Ukiya uses the Protoype Unit 00 Gate Robo, which is known for its extreme instability and unpredictability. Units 01, 02, and 03 are used by Jim Skylark, June Thunders, and Misao Sakimori respectively and amplifies their Gates even more. Aside from Ukiya, Reiko Asagiri has also operated Unit 00, and used its secret weapon, the "GRO5V" (see below), to activate her Gate of Illusions. Unit 00 was initially disabled by Reiji Kageyama's Shadow Robot at the battle atop the Tokyo Tower

Tokyo Tower

is a communications and observation tower located in Shiba Park, Minato, Tokyo, Japan. At , it is the second tallest artificial structure in Japan. The structure is an Eiffel Tower-inspired lattice tower that is painted white and international orange to comply with air safety regulations.Built in...

 by smashing its Gate Engine, but Megane found an original prototype gate engine in the Ukiya garage, reviving it. This is the same engine that was used by Ukiya to eventually defeat Kageyama in front of live national TV.

GRO5V

The Gate Robo Unit 00's secret weapon, which is practically a giant piano

Piano

The piano is a musical instrument played by means of a keyboard. It is one of the most popular instruments in the world. Widely used in classical and jazz music for solo performances, ensemble use, chamber music and accompaniment, the piano is also very popular as an aid to composing and rehearsal...

. However, Ukiya does not know how to play the piano, so Reiko Asagiri uses it when operating the Gate Robo.

UP-15

It is a modified Toyota Sports 800

Toyota Sports 800

The Toyota Sports 800 was Toyota Motor Corporation's first production sports car. The prototype for the Sports 800, called the Toyota Publica Sports, debuted at the 1962 Tokyo Auto Show, featuring a space age sliding canopy and utilizing the power train of the Toyota Publica 700, a Japanese market...

 bearing the license plate AEGIS 01, powered by a Gate Engine, and is capable of using Shun Ukiya's Gate of Gales to reach incredible speeds. When it exits, the front of Tategami High erupts in a blinding sandstorm, which is a cover as the A.E.G.I.S. hangar doors open and the car exits. Ukiya even ran the car on tracks designed for a roller coaster in an effort to hurry to the scene of a battle. It is transportable to any location via a transport truck disguised as a tanker and is available on call within three minutes. It is referred to by Megane as the "Yota-hachi." As of Gate Keepers 21

Gate Keepers 21

is a Japanese six-part sequel OVA series to the Gate Keepers animated TV series and has a darker and more serious plot than its predecessor. Some of the questions left unanswered in the TV series are answered in this sequel...

, it was the only working mecha remaining inside the ruins of A.E.G.I.S. Far East. After a brief hunt for Invaders, it was programmed by Ayane Isuzu to self destruct (by overloading its Gate Engine) to destroy Kikai Shogun and his minions.

BB5005 Electric Locomotive

An electric locomotive loaned from A.E.G.I.S. France to help stop the runaway Shinkansen possessed by Kikai Shogun. It was the fastest locomotive in France, breaking speed records (at speeds in excess of 200 km/h).

A.E.G.I.S. Bus

It is a battle carrier disguised as an old Toyota bus. Upon command, it reveals its armor and communications equipment. It is also armed on both sides with two five-barreled anti-Invader cannons and a ramming bumper. It also transported the first Gate Engine to be used, then, after adding a launch button, used as a carrier for the Gate Robo.

Vertol 3000

Twin-rotor helicopter

Helicopter

A helicopter is a type of rotorcraft in which lift and thrust are supplied by one or more engine-driven rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forwards, backwards, and laterally...

 used to transport personnel and heavy cargo, including the Gate Engine. It is not designed for high velocities (it tore to pieces when Shun warped it), and is unstable in strong winds (the Jumbo Jet Invader blew it away like a piece of paper).

Earth Defense License

An identification card that identifies an individual (man or animal) as an A.E.G.I.S. agent. The license has text that authorizes the bearer to perform tasks beyond the law and marks them as exempt from arrest and police interference.

Special Bokken Sword

Issued to Shun Ukiya, it contains a tiny Gate amplifier in its tip to supplement his kendo attacks with his Gate ability. It is retractable, thus it can be kept out of sight.

Citroen DS

Citroën DS

The Citroën DS is an executive car produced by the French manufacturer Citroën between 1955 and 1975. Styled by Italian sculptor and industrial designer Flaminio Bertoni and the French aeronautical engineer André Lefèbvre, the DS was known for its aerodynamic futuristic body design and innovative...

An ordinary Citroen car issued to Shirei for official trips outside of A.E.G.I.S. Headquarters. It has an emergency pistol in its glove compartment. It was used when Shirei and Keiko were chased by that monster #1 Hakosuka.

Lotus Seven

Lotus Seven

The Lotus Seven is a small, simple, lightweight two-seater open-top sports car produced by Lotus Cars between 1957 and 1972....

The car issued to Jim Skylark. Bears the license plate AEGIS 02.

Manga

A three-volume manga series, created by Keiji Goto and following the plot of the video game, was published by Kadokawa Shoten

Kadokawa Shoten

is a well-known Japanese publishing company based in Tokyo, Japan. Kadokawa has published both manga novels and magazines, such as Newtype magazine...

. Two volumes were released in the United States by Tokyopop

Tokyopop

Tokyopop, styled TOKYOPOP, and formerly known as Mixx, is a distributor, licensor, and publisher of anime, manga, manhwa, and Western manga-style works. The existing German publishing division produces German translations of licensed Japanese properties and original English-language manga, as well...

.

Anime

The anime series was produced by GONZO and was directed by Koichi Chigira

Koichi Chigira

is an anime director who has directed several anime series, usually working with GONZO studio.-List of works:*Full Metal Panic*Gate Keepers*Last Exile*The Tower of Druaga: the Aegis of Uruk*Brave Story...

. The network WOWOW

WOWOW

WOWOW was the first private satellite broadcasting and pay TV station in Japan. It has its headquarters on the 21st floor of the Akasaka Park Building in Akasaka, Minato, Tokyo...

 aired the 24 episode series from April 3 to September 8, 2000. In 2001, Geneon Entertainment USA

Geneon

is a Japanese music, anime and home entertainment production and distribution enterprise headquartered in Akasaka, Minato, Tokyo, Japan. Geneon has been involved in the production and distribution of several anime in Japan...

 (then known as Pioneer) aqcuired the series and released them in eight volumes on DVD and VHS. In 2004, Geneon re-released the series under the Signature Series label. In 2007, Geneon USA went out of business and left the series (including the GK21 OVA's) out-of print.

Songs

Opening theme

• • Lyrics: Junichi Sato
    Junichi Sato
    is an anime director.-TV anime:*Queen Millennia *Patalliro! *Bemubemu Hunter Kotengu Tenmaru...
    
    
  • Composition: Kohei Tanaka
    Kohei Tanaka (composer)
    is a Japanese composer, arranger and singer. He is affiliated with the music production company Imagine. He has created numerous musical scores for famous anime TV series, OVAs, movies, computer games and tokusatsu series. Tanaka was born in Ebisubashi, Osaka, Osaka Prefecture on February 14,...
    
    
  • Arrangement:
  • Artist: Yumi Matsuzawa
    Yumi Matsuzawa
    is a Japanese singer from Saitama, Saitama Prefecture. She is best known for her debut release "YOU GET TO BURNING", the opening theme for Martian Successor Nadesico, as well as the movie version's theme song "Dearest"....
    
    

Ending theme

• • Lyrics: Hiroshi Yamaguchi
  • Composition: Kohei Tanaka
  • Arrangement: Yasunori Iwasaki
  • Artist: Yumi Matsuzawa