In an alternate history of the American frontier, Andrew Jackson is a lawyer from Tennessee, William Henry Harrison has set himself up as governor of Carthage City, and Napoleon is leading an army just south of Detroit. But this is a world where folk magic actually works – and where a young boy who is the seventh son of a seventh son has the power to shape the world around him at will. This is a tale of Alvin Maker, an extraordinary man who is destined to change the world and build a magnificent Crystal City. But the Unmaker stands in his way, determined to stop Alvin from fulfilling his destiny. And with a violent war brewing between the settlers and the local tribes along the Mizzipy river, Alvin will find himself in more danger than he ever could have imagined…