Chubby Lewis, the timid but dauntless hero of The House with a Clock in Its Walls, returns in an even scarier tale of magic and mystery. Investigating the contents of Grandfather Barnavelt's ancient trunk, Lewis and Uncle Jonathan discover an old coin. Lewis hopes it's an amulet whose magic will protect him from bullies. Together with his new friend Rosa Rita, he performs a test to find the coin's power--but neither Lewis nor Rosa Rita is prepared for the astonishing and sinister events that follow.