Mr. Hollis is Bert's uncle and businessman. Mr. Hollis is unhappy with the fact that an elephant rivals his nephew, but he asks the jungle doctor for help. For Dr. Jumbo he writes a cursed prescription and Jumbo begins to lose his memory. Unable to remember even the simplest things, Jumbo wants to withdraw from the competition. But his friends prevent him and go to seek help from a dinosaur.

Ce synopsis est en anglais : nous ne l'avons pas encore traduit.