I Married a Monster from Outer Space

I Married a Monster from Outer Space is a 1958 American blackandwhite science fiction film from Paramount Pictures, produced and directed by Gene Fowler Jr. and starring Tom Tryon and Gloria Talbott.

She confronts Bill, and he eventually explains that all the females on his planet are now extinct, and that he and other males of his species are taking over human men so they can mate with Earths women, saving their race from extinction. Marge is horrified at this prospect and tries to warn others of this alien plot, but too many men in town have already been taken over, including the towns Chief of Police.Finally, her doctor Ken Lynch comes to believe her wild story, and he gathers up a posse to attack the aliens in their hidden spaceship. Although bullets cant hurt the invaders, they are defenseless against a pair of German shepherd dogs being used by the posse eventually, all the aliens are killed by the dogs. ........

Source: Wikipedia