When, prehistoric monsters attack the earth, Commander Adams is asked to head up a paramilitary scientific team, which he agrees on the condition that he is provided with the general's new high-tech space craft. Glen, the creator of the craft, insists on being part of the team, as does a bumbling fool named Marconi. Biologist Lieutenant Ann Johnson comes on as a surprise to these two chauvinists, and finally, Lieutenant Harris, who has been appointed the host of Ultraman, joins the team upon his arrivial. This featurized film is adapted from four interconnected episodes of a TV series, which covers the formation of the team and three additional monster attacks, culminating with a giant, regenerating crocodilian taken in by a little boy named Timmy, whose house is the only indication of the film's Japanese setting.