Ian Carmichael stars as the aristocratic detective Lord Peter Wimsey in this classic BBC adaptation of the novel by Dorothy L Sayers. Lord Peter Wimsey attends the wedding of Sir Charles Thorpe's son at which an extremely valuable emerald necklace belonging to Lady Wilbraham is stolen. Thanks to Wimsey's quick thinking the culprits are apprehended although the whereabouts of the jewels remain a mystery. Many years later, when a mutilated, unidentified corpse is found in the grave of the recently deceased Lady Thorpe. Wimsey investigates and becomes embroiled in an attempt to recover the necklace which was stolen many years before.