Valley Of The Zombies (1946)

Dr. Maynard (Charles Trowbridge) tells Dr. Terry Evans (Robert Livingston) and his nurse, Susan Drake (Adrian Booth), about the theft of ten pints of blood from his lab. Later, he is visited by Ormand Murks (Ian Keith), a man Maynard had once had committed to an insane asylum and who later died from an operation. Maynard learns that Murks is an example of living death whose death is counteracted only by blood.