Dunces and Dragons SpongeBob SquarePants : Season 4 Episode 14

After a freak jousting accident at a Medieval Times-style restaurant, SpongeBob and Patrick are transported to a medieval version of Bikini Bottom. There they are mistaken for great knights and sent on a quest by King Krabs to rescue his daughter, the Princess Pearl, from the clutches of the evil wizard Planktonamor. To keep them company, the King sends along Squidward, the court jester (who was recently thrown in the dungeon for not being funny)