Charlie Hall has never found a lock she couldn’t pick, a book she couldn’t steal, or a bad decision she wouldn’t make.

She's spent half her life working for gloamists, magicians who manipulate shadows to peer into locked rooms, strangle people in their beds, or worse. Gloamists guard their secrets greedily, creating an underground economy of grimoires. And to rob their fellow magicians, they need Charlie Hall.

Now, she’s trying to distance herself from past mistakes, but getting out isn’t easy. Bartending at a dive, she’s still entirely too close to the corrupt underbelly of the Berkshires. Not to mention that her sister Posey is desperate for magic, and that Charlie's shadowless, and possibly soulless, boyfriend has been hiding things from her. When a terrible figure from her past returns, Charlie descends into a maelstrom of murder and lies.

Determined to survive, she’s up against a cast of doppelgangers, mercurial billionaires, gloamists, and the people she loves best in the world—all trying to steal a secret that will give them vast and terrible power.