Chief Inspector Macdonald has been invited to a treasure hunt party at the house of the Graham Coombe, the celebrated publisher of Murder by Mesmerism. The clues of the hunt have been devised by Coombe's thriller- writer friends, disguised on the night under literary pseudonyms. The fun comes to an abrupt end, however, when 'Samuel Pepys' is found murdered in the telephone room in bizarre circumstances. Amidst the confusion of too many fake names and convoluted alibis, Macdonald and his allies in the CID must unravel a truly tangled case in this metafictional masterpiece from the beloved Golden Age author.