Former carnival performer Hubert Hawkins (Danny Kaye) and maid Jean (Glynis Johns) are assigned to protect the infant royal heir from tyrannical King Roderick I (Cecil Parker). While Jean takes the baby to an abbey, Hawkins gains access to the court by impersonating the king’s jester, unaware that the jester is really an assassin hired by scheming Sir Ravenhurst (Basil Rathbone). When Princess Gwendolyn (Angela Lansbury), falls for Hawkins, a witch secretly aids him in becoming a knight.