After a giant earthworm escapes from an Argentine science facility, the creature takes refuge near a small Texas town. Farmer Jacob Willy and his drunken neighbor Milt encounter the monster beast, with the tale of their discovery falling on deaf ears. But when tabloid reporter Tashby Price comes to town, Jacob's "Giant Worm" story takes on new life.
Meanwhile, Milt and his bar mates have their own financial plans for smuggling Mexicans across the boarder through worm tunnels they want to create with the giant night crawler.
Jacob, Milt and Tashby will have to move quickly, however, because the Argentine scientists have hired assassins to destroy the worm in order to keep sensitive research out of U.S. hands.