Gregor the Overlander

When 11-year-old Gregor lets one of his sisters go to camp instead of him, he has no idea how full of adventure his summer will turn out to be. He resigns himself to staying home and dedicating himself to babysitting and laundry, but then his 2-year-old sister, Boots, falls into an air chute. When Gregor dives in to rescue her, he discovers that they’ve landed in the Underland, a place inhabited by all sorts of strange creatures.