When Barmy Fotheringay Phipps defeats him at golf, Roberta ("Bobbie") recommends an idea for a practical joke by sneaking into Barmy's bedroom at night and puncturing the hot-water bottle with a darning needle attached to a stick.
But, when the door slams and wakes the person sleeping there, Bertie realises that it is Prof Cluj and his wife, instead of Barmy.
Prof Cluj's wife Aneta discovers the punctured hot-water bottle and they are furious with Bertie.
Tuppy Glossop is infatuated with an opera singer, Cora Bellinger, and has dropped Bertie's cousin Angela.
Her mother, Aunt Dahlia, wants this affair over with, and Jeeves produces a plan, which involves Bertie singing in public.