"One of Us Is Lying" is an American series based on the eponymous American bestseller by Karen McManus. The show's plot unfolds in a typical provincial high school. A group of teenagers stay behind after class to serve punishment for their inappropriate behavior within the school walls. As events unfold, one of the students dies under very mysterious circumstances. As a result, all the remaining survivors find themselves under police suspicion. But who is truly responsible for this shocking crime?