An alien race known as Giants on planet Gigantus are attacked by a foreign spacecraft, which prompts a team of soldiers to embark on a mission to Earth in order to wage war. The aggressors are taken aback when they realize they were giants on their home planet, they are 1/4 inch tall compared to earthlings, and the foreign spacecraft that attacked them was actually a loose screw from the Hubble telescope. The giants land in a nerdy kid's yard, and through a series of events bond to save the world.