The Quatermass Xperiment (1955)
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Professor Bernard Quatermass is in charge of a rocket mission that has gone awry. They loose contact with the spaceship and have no idea how far into space it may have traveled. When the rocket crash lands they find that only one of the three occupants, Victor Carroon, is on board; the others have simply vanished. Slowly, the surviving astronaut begins to transform into a deadly creature.