The film reduced Wells' tale to an "Ecology Strikes Back" scenario, common in science fiction movies at the time. The "food" mysteriously bubbles up from the ground on a remote island somewhere in British Columbia. Mr. and Mrs. Skinner (John McLiam and Ida Lupino) consider it a gift from God, and feed it to their chickens, which grow larger than humans as a result. Rats, wasps, and grub worms also consume the substance, and the island becomes infested with giant vermin. One night, a swarm of giant rats kill Mr. Skinner after his car tire is punctured in the forest.