An Irish character actor, Niall MacGinnis appeared in a variety of roles but was especially adept at historical dramas. Trained as a doctor, he briefly worked as a surgeon in World War II before pursuing acting. He studied at the famed Old Vic Theatre in London under John Gielgud and became well-versed in Shakespeare. His first significant role was with young director Michael Powell, who cast him in the historical drama "The Edge of the World". He worked with Powell again in the war thriller "49th Parallel", winning praise for his portrayal of a Nazi officer. Co-star Laurence Olivier was impressed, casting MacGinniss in his 1948 film "Hamlet". He had a rare leading role playing the title character in the 1953 biographical drama "Martin Luther" and would appear in several more historical films throughout the decade, including "Alexander the Great" and "Helen of Troy". MacGinnis also made his Broadway debut in the early '50s and began appearing in both American and British films. He had a memorable role in the B-movie classic "Curse of the Demon", playing the demonic Dr. Julian Karswell, and he portrayed Zeus in the 1963 fantasy classic "Jason and The Argonauts". MacGinnis had a smattering of TV appearances in the latter part of his career while continuing to appear in some of his era's most significant films like the 1965 thriller "The Spy Who Came in from the Cold".