Marcus McDermott (July 24 1881 - January 5 1929) was an Australian-born American actor who starred on Broadway and in over 180 American films from 1909 until his death.

McDermott was born Marcus McDermott in Goulburn, New South Wales to Irish parents. At age 15, while McDermott was studying at the Jesuit College of Sydney, his father Patrick died. To support his mother and sister, McDermott joined an acting troupe in Sydney. Within a year, he was discovered by illustrious stage actor George Rignold, who put him in some of his future works. Later in London, McDermott was seen by the wife of Patrick Campbell, and was cast to star opposite her in future plays. He then sailed to the United States and played on Broadway opposite her as Sir George Orreyed in The Second Mrs. Tanqeray. Back in London, New York agent and producer Charles Frohman saw McDermott's work and was impressed. He then hired him to play Sherlock Holmes and later brought him to the United States.

McDermott got his first taste of the American film industry when he was hired by Thomas Edison in 1909 to appear as a featured player at Edison's Bronx studio, in replacement of Maurice Costello, who had moved to Vitagraph, the first motion picture stock company ever formed. McDermott was then picked for a role in Les Misérables, acting with Maurice Costello and William V. Ranous. Later that year, he acted in the 1909 short Lochinvar, based on the story by Sir Walter Scott. That movie was released before Les Misérables, but he filmed the movie after Lochinvar. The next year, McDermott was casted as Ebenezer Scrooge in the short seventeen-minute silent film adaptation of Charles Dickens' work, A Christmas Carol. In 1912, McDermott starred with Mary Fuller and Charles Ogle in What Happened to Mary?, the first motion picture serial made in the U.S. The Edison Studios production consisted of twelve one-reel episodes released monthly starting on July 26, 1912 to coincide with the serial of the same name published in McClure's Ladies' World magazine.

Two years later, McDermott appeared as the lead in The Man Who Disappeared, another popular ten-chapter series that also was featured in magazines just as each chapter appeared on screen. McDermott had starred in over 140 films for Edison by 1916, and had frequently appeared in popular film magazines like Photoplay and Moving Picture World. That year, on April 20, McDermott married silent film actress Miriam Nesbitt, who costarred with him in many films such as The Man Who Disappeared. McDermott then left Edison Studios to join Vitagraph Studios. For the next decade, McDermott spent his time starring in minor and major roles in dozens of movies. McDermott died at age 47 on January 5, 1929 of cirrhosis of the liver, during surgery to treat the condition.

Marc McDermott was born Marcus McDermott (also misspelled as MacDermott after 1916), in Goulburn, New South Wales, Australia, on July 24, 1881. His father Patrick McDermott and mother Annie Massey McDermott were born in Ireland. His only sibling, younger sister May, was also born in Australia. He received his education at the Jesuit College in Sydney. When Marc was 15, his father died and he joined an acting troupe to support his mother and little sister. In 1897, he was discovered by the illustrious stage actor George Rignold and then by Mrs. Patrick Campbell in London. As her leading man, he sailed to the US and played on Broadway opposite her as Sir George Orreyed in "The Second Mrs. Tanqeray." In London, he was discovered by the New York agent and producer Charles Frohman who hired him to play "Sherlock Holmes," and then brought him to the US. After appearing with the great actor Richard Mansfield (III), he was hired by Thomas A. Edison in 1909 to appear as a featured player at the Edison Studio in the Bronx, replacing Maurice Costello (I), who had moved to Vitagraph. His first film was Misérables, Les (1909), followed by Lochinvar (1909) (Lochinvar was released first but he filmed "Les Miserables" prior to it). From 1909 through the summer of 1916, he starred in over 140 films for Edison, appearing frequently in popular early film magazines like Photoplay, Motion Picture, and Moving Picture World, voted as one of the most popular leading men during these years. On April 7, 1914, he appeared in the first-ever series in which each chapter was a complete chapter in and of itself. The ten-chapter series was Man Who Disappeared, The (1914) and the stories were featured in Popular Magazine as each chapter appeared on the screen. On April 20, 1916, in Leonia, New Jersey, he married his frequent costar Miriam Nesbitt. Later in 1916, Marc left to join the Vitagraph Studio. (to be continued).