The four-part limited series, inspired by real events, tells the story of Susan and Christopher Edwards (Olivia Colman and David Thewlis), a mild-mannered couple who went on to kill Susan's parents and bury them in their back garden, a crime that remained undiscovered for over a decade. The darkly comic drama is based on extensive research, hours of interviews, and direct access to the accused, who have always claimed their innocence.