The Quatermass Xperiment (1955)

In this chilling film based on the hit BBC-TV serial The Quatermass Experiment, a rocket ship returns to earth with a frightening surprise on board. Two of the ship's three astronauts have mysteriously vanished, while the third, Victor Carroon, is sick with an unidentifiable illness. While doctors try to help Victor recover, an investigation takes place to figure out just what happened to his comrades. As it turns out, Carroon's body has been taken over by an alien fungus that needs blood to survive. After the astronaut escapes from the hospital, he transforms into a monster, attacking everyone who gets in its way. Meanwhile, Scotland Yard detective Lomax and Quatermass, a determined scientist, attempt to track down the creature before it finds new victims. Also known as The Creeping Unknown.