When a formerly successful movie director turns up dead, beheaded by a guillotine, on the set of his latest low-budget production, detectives Barnaby (John Nettles) and Jones (Jason Hughes) wade through a multitude of suspects, including the producer and an ex-con security guard. Other possible wrongdoers in this episode of the popular British murder-mystery series include an alcoholic actor, the director's former lover and an old friend.