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- Adam Sandler as Jack Sadelstein and Jill Sadelstein in Jack and Jill (2011)
- Arnold Schwarzenegger as Jack Slater and himself in Last Action Hero (1993)
- Arnold Schwarzenegger as Adam Gibson and clone Adam Gibson in The 6th Day
- Peter Sellers as Grand Duchess Gloriana XII, Prime Minister Count Rupert Mountjoy, and Tully Bascombe in The Mouse That Roared (1959)
- Peter Sellers as Clare Quilty and Dr. Zempf in Lolita (1962)
- Peter Sellers as Group Captain Lionel Mandrake, President Merkin Muffley, and Dr. Strangelove in Dr. Strangelove or: How I Learned to Stop Worrying and Love the Bomb (1964)
- Peter Sellers as Rudolf IV, Rudolf V, and Syd Frewin in The Prisoner of Zenda (1979)
- Jane Seymour as Elena Korvin and Maria Gianelli in The Phantom of the Opera (1983 TV Movie)
- William Shatner as Johnny Moon and Notah in Commanche Blanco (1968)
- Moira Shearer as Sylvia, Daphne, Olga and Colette in The Man Who Loved Redheads (1955)
- Norma Shearer as Molly Helmer and Florence Banning in Lady of the Night (1925)
- Norma Shearer as Kathleen and Moonyeen in Smilin' Through (1932)
- Red Skelton as Rusty Cammeron, Pop Cammeron and Grandpop Cammeron in Watch the Birdie (1950)
- Red Skelton as Louis Blore and King Louis XV in DuBarry Was a Lady (1943)
- David Spade as Damien Farley and Monica in Jack and Jill.
- James Spader as John Westford and Rick Westford in Jack's Back (1988)
- Mary Steenburgen as Julie Rose, Katie McGovern, and Evelyn in Dead of Winter (1987)
- Ben Stiller as Tony Perkis and Tony Perkis Sr. in Heavyweights (1995)
- Ben Stiller as Sam Sweet and Stan Sweet in The Cable Guy (1996)
- Lewis Stone as Rudolf Rassendyll and King Rudolf V in The Prisoner of Zenda (1922)
- Donald Sutherland as Charles and Pierre in Start the Revolution Without Me (1970)
Read more about this topic: List Of Actors Who Have Played Multiple Roles In The Same Film