Timid twelve-year-old Teddy Mathews and his mother move to a small, remote desert town in eastern Washington, where the tree next door, mutated by nuclear waste, eats children and the friends Teddy makes turn out to be dead.
Twelve-year-old Sam Hill and seventeen-year-old PJ discover a scary world of goblins under the earth after one of the creatures escapes through a tunnel in the ground, and when Sam follows it back down, PJ must go underground to rescue him.