Inspector Nigel Nivens is not a nice man nor a good investigator, and he has always done everything he can to make life difficult for Inspector Witherspoon. Now, Nivens has been sent to a difficult precinct in the East End of London as penance, but he hopes to redeem himself by solving a murder case. But there's one big problem with his plan—Niven's distinct antique pistol is found at the scene of the crime. Despite their mutual dislike for Nivens, Mrs. Jeffries and Inspector Witherspoon know the man isn't a cold-blooded killer, and in their 39th case, they'll just have to prove it.