Magic is fading from the Wild Wood. To renew it, goblins must perform an ancient ritual involving the rarest of their kind—a newborn changeling. But when the night arrives to trade a human baby for a goblin one, something goes terribly wrong. After laying the changeling in a human infant’s crib, the goblin Kull is briefly distracted. By the time he turns back, the changeling has already perfectly mimicked the human child. Too perfectly: Kull cannot tell them apart, so he leaves both babies behind.