Books in the Underland Chronicles series

Spies have reported the sighting of a Rat King in the Underland. But when Gregor eventually comes face to face with the Rat King, he finds he is unable to kill him. Gregor's heart tells him he's making the right decision. Will it be one he lives to regret?

When eleven-year-old Gregor falls through a grate in the laundry room of his apartment building, he hurtles into the dark Underland, where spiders, rats and giant cockroaches coexist uneasily with humans. This world is on the brink of war, and Gregor's arrival is no accident. Gregor has a vital role to play in the Underland's uncertain future.