Michie and her best friend Trissa grew up like sisters in a ramshackle duplex owned by their single moms. But now that they're sixteen, the differences in identity and experience have caused a rift. Michie's an introvert obsessed with a book called A Girl's Guide to Murder, and her mom has an organic weed and mushrooms grow-op in the basement. Shiny, extroverted Trissa, on the other hand, dances at the hottest nightclub in town, while her mother holds an ultra-responsible job at City Hall.

One night, Michie wakes up one night to find Trissa missing, having left only a cryptic note. The cops write her off as a party girl who's probably already met a foul end, and the mothers fall apart from fear and grief, but Michie refuses to believe it.

Enlisting help from her friend Anwar, who she's been in love with forever, Michie sets off to look for Trissa, knowing she's the only one who will. The search takes them into unfamiliar, dangerous territory: the back rooms of Trissa's luxury nightclub, dark alleyways, the online sex industry, and rural cottage country.

As she begins to unravel Trissa's secrets against a backdrop of cold authority figures, shady characters, and a serial killer who's been active in the city, Michie knows she's plunging into danger--but she's determined to find her chosen sister and to bring her home safely.