Set in Wales, Death Valley follows the unlikely crime-solving partnership between eccentric national treasure John Chapel (Spall), a retired actor and star of hit fictional detective TV show Caesar, and disarming detective sergeant Janie Mallowan (Keyworth). Thrown together by the murder of John’(⛴)s neighbor, John and Janie are an odd, yet hilarious duo with opposing instincts, and each week they get to the bottom of gripping murders.