Sally St. John Brainerd is on the run from the authorities, who want to question her about her possible involvement in her father's murder. FBI Special Agent James Quinlan goes undercover in the picturesque town of The Cove-home of the World's Greatest Ice Cream-where Sally seeks sanctuary. But The Cove and its elderly residents harbor sinister secrets of their own. After Quinlan and Sally discover two dead bodies, Sally vanishes, and Quinlan turns to his partner Dillon Savich to rescue her from a place where no one should be held. Quinlan discovers she is indeed the key to a murder-but whose murder?