Stranger Things meets The Walking Dead in this chilling novel based on the terrifying urban legend about a video game created by the government for psychological warfare. October, 1982. Forced to move to the quiet seaside town of Tasker Bay by her mother, the only thing on high schooler Andi's mind is saving up enough money to return to her old stomping grounds in Silicon Valley. Her self-taught skills with all things electronic make her a perfect fit for a job at the dingy local arcade where she can tune out from life and bankroll her eventual escape.

Pining over the distant and aloof Andi is Ro, the son of Tasker Bay's sheriff, who begins spending more time at the arcade. Despite promising herself she wouldn't get attached to anyone in town, Andi finds herself opening up to the thoughtful, like-minded Ro.

When Polybius--a new bleeding-edge game of unknown origin arrives--the shop is suddenly overwhelmed with players fighting for time on the machine. Seemingly overnight, a virus-like epidemic grips Tasker Bay while a violent coastal storm rolls in, isolating it from the outside world. People begin experiencing fits of anger, paranoia, and hallucinations--no one can be trusted. After a grisly act of violence goes unsolved, the town descends into chaos. Is the arrival of this mysterious game and the disorder in Tasker Bay a coincidence? Convinced the dire situation is somehow linked to Polybius, Andi and Ro desperately search for clues that might stop the spread before they, too, begin experiencing side effects...