Like the last Wodehouse I read, this is more like Damon Runyon than later Plum. I suspect that this was written when Wodehouse first visited America and was trying to break into the American markets (it would be interesting to compare this impression with Wodehouse's biography and see what it has to say about the Runyonesque qualities of these early novels). The Little Nugget of the title refers to the only son of an American millionaire, the nickname given to him by the American hoodlums who want to kidnap him and hold him for ransom. Wodehouse spends a lot of verbiage describing how odious the Little Nugget is, but yet the plot isn't really about the kid's nature, but his value.
There was one bit that was perfect, especially considering I had just read The Friendly Shakespeare. One of the characters is mistaken for the famous American criminal "Smooth Sam Fisher." Actually, he's not just mistaken--the other character insists that he is Sam Fisher. The response? "Verily, some have greatness thrust upon them." Wodehouse was quite a lover of Shakespeare, and it would be quite a large project to list all the Shakespearean allusions, puns, and outright quotes in his books . . . but it's certainly fun when you do catch one yourself.