Ex-Detective Inspector Daniel Hawthorne and his sidekick, author Anthony Horowitz, are invited to an exclusive literary festival on Alderney, an idyllic island off the south coast of England. Upon arrival, they meet the festival’s other guests --- an eccentric gathering that includes a bestselling children’s author, a French poet, a TV chef turned cookbook author, a blind psychic and a war historian --- along with a group of ornery locals embroiled in an escalating feud over a disruptive power line. When a local grandee is found dead under mysterious circumstances, Hawthorne and Horowitz become embroiled in the case. The island is locked down, no one is allowed on or off, and it soon becomes horribly clear that a murderer lurks in their midst. But who?