When 51-year-old Nathan Smith is found in his bed with a hole in his head, it's hard not to imagine Nathan's young bride, Mary, as the one with her finger on the trigger. Even her lawyer thinks she's guilty. But Mary Smith is entitled to the best defense she can afford, so Spenser hires on. Mary claims she was watching TV in the other room when the murder occurred. But the couple was seen fighting at a high-profile cocktail party earlier that evening and the prosecution has a witness who says Mary once tried to hire him to kill Nathan. What's more, she's too pretty, too made-up, too blonde, and sleeps around -- just the kind of person a jury loves to hate. Spenser's up against a wall -- leads go nowhere and no one knows a thing. Then a young woman, recently fired from her position at Smith's bank, turns up dead. Suddenly Mary's vacant past starts looking meaner and darker and Spenser's got to watch his back.