Cabaret Courage Courage the Cowardly Dog : Season 4 Episode 22

"Wrath of the Librarian" Courage finds a two year overdue book. When he decides to return it, he does not have enough money for the $10,000 fee, so the librarian casts a spell on Muriel and Eustace, turning them into the characters from the book until Courage finds enough money to pay the fee for the book.