I Married a Monster from Outer Space (1958) - eviltoast

SHUDDERY THINGS FROM BEYOND THE STARS, HERE TO BREED WITH HUMAN WOMEN!

Aliens are slowly switching places with humans – one of the first being a young man about to get married. Slowly, his new wife realizes something is terribly wrong, and her suspicions are confirmed when her husband’s odd behaviour begins to show up in other townspeople.

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