Dan Seymour was born Daniel Seymour Katz in Chicago, Illinois. He attended Senn High School in Chicago and graduated from the University of Chicago with a B.S. in Fine Arts.

Career 

While in college, he worked in many school plays and also worked at night as an emcee at various Chicago night clubs, becoming quite successful. He moved to Hollywood, where his rotund build (265 lb or 120 kg) and swarthy looks made him perfect for a Hollywood villain. He played Humphrey Bogart's character's enemy, Vichy French Captain Renard, in To Have and Have Not. In the 1952 movie Mara Maru, he played opposite Raymond Burr and Errol Flynnwhose character was named Mason. He later appeared in 7 episodes of Perry Mason, which starred Burr; the episodes spanned the entire nine-year run of the popular series. During the first season in 1957 he played Harry Marlow in "The Case of the Silent Partner." In the final season in 1965 he played Nappy Tyler in "The Case of the Carefree Coronary." He made four appearances in The Untouchables, and three on Adventures of Superman. He also appeared onMolle Mystery Theater and many other television series.

Source: Wikipedia