Claim: Marlon Brando played a role.

Julius Caesar is a 1953 epic Metro-Goldwyn-Mayer film adaptation of the play by Shakespeare , directed by Joseph L. Mankiewicz , who also wrote the uncredited screenplay , and produced by John Houseman . The original music score is by Miklós Rózsa . The film stars Marlon Brando as Mark Antony , James Mason as Brutus , John Gielgud as Cassius , Louis Calhern as Julius Caesar , Edmond O'Brien as Casca , Greer Garson as Calpurnia , and Deborah Kerr as Portia .