Steven Williams is an American actor in films and television. He is known for his roles as Captain Adam Fuller on 21 Jump Street, Lt. Jefferson Burnett on The Equalizer, Det. August Brooks on L.A. Heat, X on The X-Files, Russell "Linc" Lincoln in Linc's, and Rufus Turner in Supernatural. 

He is known for his role as Captain Adam Fuller on the Fox Network's TV series 21 Jump Street from 1987–91. He played Lt. Burnett on the CBS drama series The Equalizer in 1985. He later played Det. August Brooks on the short lived TNT series L.A. Heat in 1996. Steven also had a recurring role as X on the Fox hit science fiction series The X-Files. He starred as Russell "Linc" Lincoln in Linc's. He later played Rufus Turner in Supernatural.

He appeared in The Blues Brothers (1980) as Trooper Mount. Other film roles include playing Nester in the 1985 sequel film Missing in Action 2: The Beginning, and in the 1993 horror film Jason Goes to Hell: The Final Friday as a bounty hunter named Creighton Duke. Steven has also made many guest starring appearances on television shows, including The Dukes of Hazzard, The A-Team, Booker, MacGyver, Stargate SG-1, Martin, Veronica Mars, The Bernie Mac Show, Criminal Minds and iZombie.

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