This is one of a series of vintage AIP horror titles released some time ago as part of an R2 DVD collection entitled "The Arkoff Library", though the copy I watched was actually culled from an AMC TV broadcast (with constant streaming advertisements of upcoming shows and pictures!); others include THE SHE-CREATURE (1956), BLOOD OF Dracula (1957) and HOW TO MAKE A MONSTER (1958)  all of which I have acquired in time for my ongoing Halloween challenge. Thematically, the film is a variation on the classic INVASION OF THE BODY SNATCHERS (1956) with a small town gradually taken over (though not by an alien organism but rather a vanished  and, typically, superior  civilization); despite the sensationalistic title, the creatures  'possessing' their victims through small punctures at the back of the neck  are never actually seen, leading to a wonderful POV shot (perhaps the film's highlight) depicting an attack on the hero's girlfriend. The leader of the 'invaders' is actually a bearded old man  only ever shown in silhouette  residing in a cone-shaped rocket! The end result is not too bad though hardly a classic of its familiar kind or genre and obviously cramped by the low budget and necessary compactness (running a mere 56 minutes); interestingly, the film's director is the burly Orson Welles-lookalike sleazeball from DEMENTIA (1955).