After you with the pistol, Kyril Bonfiglioli
Written in the P.G. Wodehouse (but where all the jokes are deeply, deeply inappropriate) and with the plotting of a spy novel, this is as much politically unacceptable fun as you can have aside from having breakfast with my wife's grandparents (recommended). Best enjoyed by those of you who already have a working knowledge of P.G.Wodehouse, especially the Jeeves books and the Mulliner stories, this isn't something you can read aloud to mother or quote from liberally in the office. It also won't excerpt well on social media. However, each chapter ends on a strong note, he barely drops a single whiffer in 180 pages, and you are guaranteed to laugh or you get your money back. It's not actually as good as P.G., of course, and if you are currently hankering to hear that Bertie Wooster toddled down to the Drones club to toss cards into a hat with some of the better element, I recommend you flee to Right Ho, Jeeves! (US link) like the hart that panteth after water. For the rest of you, Kyril Bonfiglioli's Mortdecai trilogy beckons.
Don't Point That Thing at Me: The First Charlie Mortdecai Novel (US link)
After You with the Pistol: The Second Charlie Mortdecai Novel (US link)
Something Nasty in the Woodshed: The Third Charlie Mortdecai Novel (US link)