Fifteen-year-old Lydia, resigned to a boring summer in Halifax, is thrilled when Megan and her totally hot brother, Sam, move in across the street. But their rude and hostile mother, Mrs. Swicker, is strangely protective, and does everything she can to stop Lydia and her older sister, Jilly, from getting anywhere near her kids. One day Lydia accidentally stumbles across something very puzzling in the Swickers' basement. Determined to find some answers, Lydia enlists the help of Jilly. But the further they investigate, the more bizarre the discoveries. Lydia's suspicions about Mrs. Swicker are mounting, but she has no idea what a twisted, dangerous secret she has uncovered until it's too late.