When obscure crime writer Ethelred Tressider vanishes from his home, his indefatigable agent, Elsie Thirkettle, is soon on his trail. Finding him proves surprisingly easy. Bringing him home is another matter. Having followed Ethelred to a hotel in the French Loire, she find herself confined there with him after a prominent philatelist is murdered. Elsie is torn between her natural desire to interfere in the police investigation and her urgent need to escape to the local chocolatier. Ethelred, meanwhile, seems to know more about the murder than he is letting on. It does not help his peace of mind when two further guests are poisoned.Finally the time comes when Elsie must assemble the various suspects in the Dining Room, and reveal the killer's true identity ...