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- Eric Idle as Sir Robin the Not-Quite-So-Brave-as-Sir Launcelot, the Corpse Collector, Roger the Shrubber, Peasant #1, the First Swamp Castle Guard, Concorde, and Brother Maynard in Monty Python and the Holy Grail (1975)
- Jeremy Irons as Beverly Mantle and Elliot Mantle in Dead Ringers (1988)
- Jason Isaacs as Mr. Darling and Captain Hook in Peter Pan (2003)
Read more about this topic: List Of Actors Who Have Played Multiple Roles In The Same Film