A slew of Broadway veterans are gearing up to go into the ring with heavyweight champ Muhammad Ali. The new Stephen Frears movie, Muhammad Ali's Greatest Fight, explores Ali’s battle with the Supreme Court after he was drafted to fight in Vietnam and refused to go due to his beliefs against the controversial war. The film stars Broadway alums Christopher Plummer, Frank Langella, Benjamin Walker, Danny Glover, Dana Ivey and Kathleen Chalfant, as well as Barry Levinson and Ed Begley Jr. The film, which utilizes archival footage of Ali, debuts on HBO on October 5. Check out the first trailer below.