The Quatermass Xperiment (The Creeping Unknown in the United States) is a 1955 British science-fiction/horror film. Made by Hammer Film Productions, it was based on the 1953 BBC Television serial The Quatermass Experiment. Its success was a key factor behind Hammer turning towards the horror film productions for which they became particularly noted as a film studio. It was directed by Val Guest, and stars Brian Donlevy as the eponymous Professor Bernard Quatermass.
The plot of the film involves the return to Earth of astronaut Victor Carroon, who has become the first man in space in a rocket ship of Quatermass's design. However, it becomes very clear that something infected Carroon during the flight, and he rapidly begins mutating into an alien organism which, if it spores, will destroy humanity. Quatermass and his associates have just a few hours to track the creature down and prevent an apocalypse.
The film was often criticised by Nigel Kneale, the creator of the Quatermass series and author of the original television serial upon which The Quatermass Xperiment was based. Kneale particularly disliked Donlevy's performance in the title role, but despite his comments the film is seen by some reviewers as a classic of the genre. In his book British Science Fiction Cinema, media studies lecturer I. Q. Hunter describes it as "the key British science fiction film of the 1950s." Hunter, p. 8.
A missile, launched by the team led by Prof. Quatermass, lands in the English countryside. Of the three members of the crew, two have mysteriously disappeared. The third one, barely alive, undergoes an horrible metamorphosis turning into a monstrous "thing". When he breaks out and, chased in vain by inspector Lomax, starts killing humans and animals to feed his transformation, Quatermass realizes that this is the way chosen by an alien form of life to invade the Earth. Written by Stefano Cristiani
