Once again Lionel Townsend, Beef's Dr. Watson, faithfully records the redoubtable Sergeant's escapades. Beef has left the Braham police and gone into business for himself. Lionel Townsend loyally comments: "He had already hinted to me that he was thinking of retiring from his post as a country police sergeant, but I had never dreamed that the luck he had had in stumbling on the solutions to a couple of murder mysteries would lead him into anything of this sort Poor old Beef!. That he should have kept his job at Braham had surprised me, for his fondness for the local pubs was a byword. That he should have been the means of tracing two murderers was a miracle. That he should be able to earn a living as a private investigator was beyond credulity."

But Beef does get a client: Stewart Ferrars, who has been arrested for the Sydenham Murder. Beef is hired by Stewart's brother Peter to prove Stewart innocent of the murder of Dr. Benson, who has been found stabbed in the throat in the library of Peter's gloomy Victorian mansion, The Cypresses. An ornamental dagger with Peter's fingerprints on it has been left on a table near the dead man's armchair.