Serious Sam II is a science fiction

Science fiction

Science fiction is a genre of fiction dealing with imaginary but more or less plausible content such as future settings, futuristic science and technology, space travel, aliens, and paranormal abilities...

 first-person shooter

First-person shooter

First-person shooter is a video game genre that centers the gameplay on gun and projectile weapon-based combat through first-person perspective; i.e., the player experiences the action through the eyes of a protagonist. Generally speaking, the first-person shooter shares common traits with other...

 video game released for the PC

Personal computer

A personal computer is any general-purpose computer whose size, capabilities, and original sales price make it useful for individuals, and which is intended to be operated directly by an end-user with no intervening computer operator...

 and Xbox

Xbox

The Xbox is a sixth-generation video game console manufactured by Microsoft. It was released on November 15, 2001 in North America, February 22, 2002 in Japan, and March 14, 2002 in Australia and Europe and is the predecessor to the Xbox 360. It was Microsoft's first foray into the gaming console...

 and the sequel to the 2001

2001 in video gaming

-Events:* Academy of Interactive Arts & Sciences hosts the 4th Annual Interactive Achievement Awards; inducts John Carmack of id Software to the AIAS Hall of Fame...

 computer game Serious Sam

Serious Sam

Serious Sam is the first game in the Serious Sam series. It is a first-person shooter created by the Croatian development house Croteam...

, making it the second game in the Serious Sam series

Serious Sam (series)

-Games:* Serious Sam * Serious Sam II * Serious Sam 3: BFE...

. It was designed and developed by Croteam

Croteam

Croteam is a video game developer established in Zagreb, Croatia in 1993, initially as a "garage games" company. They only had six employees and four contractors for the development of Serious Sam in 2001.-Company history:...

 and was released on October 11, 2005. The game was published by 2K Games

2K Games

2K is a global developer, marketer, distributor and publisher of interactive entertainment software games. 2K Games is a subsidiary of Take-Two Interactive, which also owns Rockstar Games notable for the Grand Theft Auto series...

, a Take-Two Interactive

Take-Two Interactive

Take-Two Interactive Software, Inc. is a major American publisher, developer, and distributor of video games and video game peripherals. Take-Two wholly owns 2K Games and Rockstar Games. The company's headquarters are in New York City, with international headquarters in Windsor, United Kingdom...

 subsidiary. While the game was originally released only for Windows

Microsoft Windows

Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...

 and the Xbox

Xbox

The Xbox is a sixth-generation video game console manufactured by Microsoft. It was released on November 15, 2001 in North America, February 22, 2002 in Japan, and March 14, 2002 in Australia and Europe and is the predecessor to the Xbox 360. It was Microsoft's first foray into the gaming console...

, a Linux

Linux

Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...

 version of the game client and the game's content editor, Serious Editor 2, was later released and is in beta.

In the single-player campaign, the player assumes the role of hero

Hero

A hero , in Greek mythology and folklore, was originally a demigod, their cult being one of the most distinctive features of ancient Greek religion...

 Sam "Serious" Stone in his adventures against the forces of the extraterrestrial

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:...

 overlord, "Mental", who seeks to destroy humanity.