The Fabulous Feud of Gilbert & Sullivan — Jonah Winter

Caldecott Medalist Richard Egielski teams up with Jonah Winter for a story of friendship, fights, and musical comedy
Welcome to Topsy-Turvydom, a magical kingdom (well, more like an opera stage) full of pirates, policemen, fairies, and fake mustaches Mr. Gilbert and Mr. Sullivan have ruled this kingdom together in peace, but one day, Mr. Sullivan decides he's had enough. Every opera they write is the same silly old story, and he's ready for something different. Something serious
Mr. Gilbert is stunned. He's lost his business partner and his best friend, and he needs a brilliant idea in order to get him back.