O Rei Artur sai à procura de cavaleiros que o acompanhe em uma atabalhoada jornada histórica: A busca do Santo Graal. Aparecem então Sir Lancelot, o Bravo; Sir Robin, o Não-Tão-Bravo-Quanto-Sir-Lancelot; Sir Galahad, o Puro, entre outros personagens surreais. Escrita pelo genial grupo de comédia britânico Monty Python, a trama do longa satiriza diversos eventos históricos ocorridos na Idade Média.
King Arthur / Voice of God / Middle Head / Hiccoughing Guard
Second Swallow-Savvy Guard / The Black Knight / Peasant 3 / Sir Launcelot the Brave / Taunting French Guard / Tim the Enchanter
Dead Collector / Peasant 1 / Sir Robin the Not-Quite-So-Brave-as-Sir Launcelot / First Swamp Castle Guard / Concorde / Roger the Shrubber / Brother Maynard
Patsy / Green Knight / Old Man from Scene 24 (Bridgekeeper) / Sir Bors / Animator / Gorilla Hand
Dennis's Mother / Sir Bedevere / Left Head / Prince Herbert / Voice of Cartoon Scribe
First Swallow-Savvy Guard / Dennis / Peasant 2 / Right Head / Sir Galahad the Pure / Narrator / King of Swamp Castle / Brother Maynard's Brother / Leader of The Knights Who Say NI!
The Witch
Zoot / Dingo
First Monk / Singing Minstrel / Page Crushed by the Rabbit / Peasant #4
Old Crone
Diretor