One of Our Dinosaurs is Missing is a 1975 British comedy film, which is set in the early 1920s, about the theft of 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...

 skeleton

Skeleton

The skeleton is the body part that forms the supporting structure of an organism. There are two different skeletal types: the exoskeleton, which is the stable outer shell of an organism, and the endoskeleton, which forms the support structure inside the body.In a figurative sense, skeleton can...

 from the Natural History Museum

Natural History Museum

The Natural History Museum is one of three large museums on Exhibition Road, South Kensington, London, England . Its main frontage is on Cromwell Road...

. The film was produced by Walt Disney Productions and released by Buena Vista Distribution Company. The title is a parody of the film title One of Our Aircraft Is Missing

One of Our Aircraft is Missing

One of Our Aircraft is Missing is a 1942 British war film, the fourth collaboration between the British writer-director-producer team of Michael Powell and Emeric Pressburger and the first film they made under the banner of The Archers...

. The film was based on the 1970 novel The Great Dinosaur Robbery

The Great Dinosaur Robbery

The Great Dinosaur Robbery is a now out-of-print book released in 1970 and written by David Eliades and Robert Forrest Webb under the pseudonym of David Forrest...

by David Forrest (pseudonym

Pseudonym

A pseudonym is a name that a person assumes for a particular purpose and that differs from his or her original orthonym...

 of David Eliades and Robert Forrest Webb).
Escaping from China with a microfilm of the formula for the mysterious "Lotus X", Lord Southmere, a Queen's Messenger

Queen's Messenger

The Corps of Queen's Messengers are couriers employed by the British Foreign and Commonwealth Office. They hand-carry secret and important documents to British embassies and consulates around the world. Many Queen's Messengers are retired Army personnel...

, is chased by a group of Chinese spies.

Back in London, Lord Southmere manages to escape from a taxi driver who is trying to kidnap him, and then runs into the Natural History Museum

Natural History Museum

The Natural History Museum is one of three large museums on Exhibition Road, South Kensington, London, England . Its main frontage is on Cromwell Road...

.