Hester has always wanted to be a court jester, but it's always been a man's job, so she knows she has little chance of achieving her dream. She's be much better off trying to be a lady-in-waiting like her mother.
Hester's best friend, Calvin, is the current jester, but after slipping on goose grease and banging his head, Calvin has a problem. His short-term memory is terrible. He gets his jokes mixed up, and he can't remember punchlines. To add to his woes, his muscles are starting to stiffen up, making it difficult for him to caper and do acrobatic tricks.
When he worries about how he can cope at the king's special All Fools dinner, Hester assures him that she can help. She'll hide under the table and hold flash cards for him so he can get his jokes right. But things don't go as planned, and the special powder Hester puts down Calvin's tunic to help him caper has him knocking himself out.
Now it's up to Hester. Can she impress the king enough to become the new court jester?