WINNER OF BEST NOVEL IN 2016 NEBULA AWARDS FINALIST FOR BEST NOVEL IN THE 2017 HUGO AWARDS Childhood friends Patricia Delfine, a witch, and Laurence Armstead, a mad scientist, parted ways under mysterious circumstances during middle school. But as adults they both wind up in near-future San Francisco, where Laurence is an engineering genius and Patricia works with a small band of other magicians to secretly repair the world's ever growing ailments. But something is determined to bring them back together—to either save the world, or end it.