THE IN-LAWS

In Chen’s (An Intangible Affair, 2017, etc.) latest series installment, Bostonian amateur detective and biologist Ann Lee sets out to prove the innocence of a friend accused of murder.

Ann knows that potential in-laws can be burdensome; after all, her former boyfriend’s stepmother turned out to be a killer in a previous book in this series. So she understands when her friend Betty Foreman is stressed by her fiance Peter Shi’s mom, Emily. Betty thinks that the overprotective parent has made her son a “mama’s boy”; indeed, Peter takes his mother’s side whenever she and Betty have an argument. It’s not surprising that Betty is a suspect after Emily’s body is discovered at the bottom of a flight of stairs. The dying woman’s 911 call, in which she named Betty as her murderer, only solidifies the police’s case. But Ann believes Betty’s claim of innocence; she says that she argued with Emily on the day in question but left when the old woman threw a vase at her. With Betty’s trial imminent, Ann decides to try to debunk the damning evidence against her. Luckily, she has help from her best friend and partner at their detective agency, Fang Chen, who’s a chemist as well. The investigation involves interviewing Emily’s neighbor, who called 911 regarding the women’s loud squabble, and talking to Emily’s sister in Hong Kong. As in preceding novels in this series, Chen delivers a brisk story with a simple but tight mystery that’s often heavy on dialogue. Along the way, the author has Ann meticulously develop a theory to fit the evidence—that is, one in which Betty isn’t guilty of murder. Romantic relationships also complicate matters, as Ann is currently dating Betty’s older brother, Seth Foreman. Ann’s investigation, along with Fang Chen’s input, has an organic feel: Every conjecture has a clear source, and nothing that she deduces feels like a wild guess. Still, the ending, while plausible, gets a bit convoluted as Ann juggles multiple theories of the crime.

Another tale of incisive sleuths that’s short but thoroughly enjoyable.