Though he has learned to read, write and do mathematics while living in the castle, Jemmy is beaten several times a day and longs for the freedom he had on the streets.

They come across a girl named Betsy searching for her lost dancing bear, Petunia, and she directs them to the river where they find a kind man with a wagon full of potatoes.

Betsy earns a few coins with her bear, Captain Nips boils the potatoes and sells them, and Horace and Jemmy head down to the sewer to catch some rats.

When they return to Captain Nips, Horace reveals himself as a prince and suggests that the potato man collect the reward for capturing the whipping boy.

Fleischman's book was adapted in the 1994 Disney Channel television film Prince Brat and the Whipping Boy starring Truan Munro, Nic Knight, George C. Scott, Vincent Schiavelli, Mathilda May, and Kevin Conway,[1] and directed by Sydney MacArtney.