10-year-old Lewis Barnavelt is sent to Michigan to live with his uncle, Jonathan Barnavelt, after the loss of his parents. Lewis discovers his uncle is a warlock and follows him into the world of sorcery and magic. Meanwhile, evil wizard Isaac Izard aims to bring the Apocalypse upon the world by creating a magical clock filled with black magic. Before his passing, he manages to hide it inside the walls of the house Jonathan currently lives in. Now Lewis and his uncle must find the clock and stop the end of the world.