Film screenshot (Warner Bros.) · Public domain

Blacklisted in the 1950s for his political associations and shut out of studio work, he turned the setback into a second career, becoming one of Hollywood's most sought-after acting coaches; his students included Jack Nicholson, James Dean, Barbra Streisand, Cher, and Leonard Nimoy. He returned to acting himself in the 1960s, building a long run of character roles once the blacklist lifted.