In this timely and terrifying thriller from the author of the popular FBI K-9 novels, a woman with a side gig offering relationship advice on Twitch learns just how dangerous online anonymity can be . . .

Chicago physical therapist Krista Evans finds that her clients rely on her life and love advice just as much as on her hands-on work, so why not share it on the live-streaming platform Twitch? Her friend Hailey Swanson, an inveterate gamer, is willing to help Krista build her presence and cohost a biweekly show. A Word from the Wise is born . . .

Taking real-time questions from chat participants proves more popular than Krista thought possible, and their follower count—and income—grow. But not all attention is wanted, as she soon discovers. An account with the username Chase547 becomes enraged when Krista and Hailey suggest he stop pursuing a woman who constantly rebuffs him. He amps up his efforts, even when he's piled on by other followers, throwing their chats into chaos.

Unnerved by Chase547's obsession, Krista turns to law enforcement, but the little information she's able to give the Chicago PD isn't enough to start an investigation.

Soon, Krista notices things missing at home and feels as if she's being watched. And when Chase547 begins to leave clues in real life proving what he's capable of, she begins to fear for her safety. Chase547 has more than one way to make his presence known—and this time it won't be from behind a screen . . .