POSSIBLE SPOILERS Government scientist Professor Bernard Quatermass (BRIAN DONLEVY) sends a rocket into space containing three astronauts. Radio contact is lost and later it crash lands in the English countryside. Two of the crew members are missing, but the survivor, Victor Carroon (RICHARD WORDSWORTH) is slowly being taken over by an alien fungus that feeds on the blood of animals and human-beings.
In a bid to win audiences away from their TV sets (something that was a real threat to cinemas at the time), Hammer elected to film the popular BBC serial THE QUATERMASS EXPERIMENT (the E was replaced with X in order to emphasise it's X certificate), which was the creation of writer Nigel Kneale. The gamble payed off and Hammer had a box office hit on their hands in 1955.
Seen today, THE QUATERMASS XPERIMENT is obviously very tame in comparison to modern day sci-fi and horror films, most of it's shock sequences occur off screen with the camera cutting away and harping back on reaction shots. Yet it is a milestone in the development of British horror cinema and along with the company's THE CURSE OF FRANKENSTEIN, it spawned this country's horror boom of the 1950's and 60's. Richard Wordsworth's Carroon is one of the most sympathetic monsters in British horror and there is a classic scene at the London docks where the former is hiding out in an abandoned boat and is awakened by a little girl who is having a pretend picnic with her dolly. Unaware of the true horror that's going on, the little girl naively asks Carroon if he wants to join them. One can see that Carroon is fully aware of what would happen if the girl touches him and runs away accidentally breaking her dolly.
Wordsworth is brilliant as Carroon and so is Brian Donlevy as Quatermass while director Val Guest's documentary approach gives the picture a sense of conviction.