The eleven-year-old Gregor sets off to save his two-year-old sister, who has fallen into a ventilation shaft in the basement of their apartment building in New York, and ends up in the dark Underland, deep beneath the city. There, people live in an uncertain coexistence with giant spiders, bats, cockroaches, and rats - but fragile peace will soon be shattered.

Gregor does not want to participate in the war. He just wants to find his way home. But when he discovers that a prophecy predicts his own role in the future of the underground world, he realizes that this may be the only way to solve the great mystery of his life: his father's disappearance. This quest will change both himself and the Underland.

"Gregor the Overlander" is the first book in "The Underland Chronicles" series. A series that combines adventure, suspense, humor, and tenderness, courage and moral dilemmas in a dark land of wonders.