A classic B-movie, elevated greatly thanks to a solid central performance from the dependable Peter Graves (The Night of the Hunter, TV's "Mission Impossible). After a brilliant nuclear scientist Douglas Martin (Graves) is abducted by aliens, he attempts to warn the government of the aliens' nefarious plans to exterminate humanity using giant insects and reptiles, only to be met with understandable skepticism from the FBI. Left to defend the planet on his own, Martin must use his intellect to concoct a plan that will stop the aliens in their tracks before they get a chance to carry out their scheme.