In a world ruled by magical perfume, the last scion of an ancient bloodline carries the power to bend mind, body, and emotion through fragrance. When a crisis in the royal court threatens to tear the kingdom apart, a silver-eyed spymaster makes a dangerous bargain with her: craft a legendary perfume to save the realm, and claim the life and fortune that should always have been hers.

But the perfume's lost ingredient is buried in the kingdom's dark underbelly, and as the threats on her life escalate, so does the scorching tension between her and the aristocrat she's determined to hate. Every bargain has a cost, and this one may demand more than either of them can pay.