I Married a Monster from Outer Space

This science-fiction film from the 1950s follows a bunch of aliens who have descended upon Earth in hopes of taking over the planet and the universe by producing large quantities of alien-human offspring. Disguised as a human, one of the other-worldly beings (Tom Tryon) ties the knot with a naïve human woman (Gloria Talbott). Although she's clueless at first, she eventually learns of their scheme and does all she can to stop it.