When obscure crime writer Ethelred Tressider vanishes, his dogged literary agent, Elsie Thirkettle, is soon on his trail. Finding him (in a ramshackle hotel in the French Loire) proves surprisingly easy. Bringing him home proves more difficult than expected but (as Elsie observes) who would have predicted that, in a hotel full of stamp collectors, the guests would suddenly start murdering each other? One guest is found fatally stabbed, apparently the victim of an intruder. But when a rich Russian oligarch also dies, in a hotel now swarming with policemen, suspicion falls on the remaining guests. Elsie is torn between her natural desire to interfere in the police investigation and her urgent need to escape to the town's chocolaterie. Ethelred, meanwhile, seems to know more about the killings than he is letting on. Finally the time comes when Elsie must assemble the various suspects in the Dining Room, and reveal the truth ...