Cox made his debut in the 1972 film
Deliverance. In one scene, he plays the instrumental "
Dueling Banjos" on his guitar with a banjo-playing mountain boy, played by child actor
Billy Redden. He was hired for the role because he could play the guitar. Cox published his
autobiography in 2012, recounting his experiences making the film. In 1974, Cox starred in the short-lived family-oriented series entitled ''
Apple's Way, created by Earl Hamner, creator of The Waltons. He also appeared as Mr. Webb in a television production of Our Town. In 1977, he appeared in the episode "Devil Pack" from the series Quinn Martin's Tales of the Unexpected. In 1984, 12 years after Deliverance
, Cox again played a member of a small group of men who are lost, this time in the Nevada desert, and being chased by bloodthirsty locals in the low-budget film Raw Courage''. One of Cox's roles was that of Dr. John Gideon during the final season of the television medical drama
St. Elsewhere. His character was
mooned by Dr. Donald Westphall (
Ed Flanders) at the end of the third episode of season six. Cox's first role in a big-budget film came in 1984 as Lt. Andrew Bogomil in
Beverly Hills Cop, and he returned to the role in
Beverly Hills Cop II in 1987. That same year, Cox appeared in the
Paul Verhoeven film
RoboCop as corporate arch-villain Richard "Dick" Jones. In 1986, Cox played the mayor in
season 3, episodes 1 and 2, "Death Stalks the Big Top", of the TV series
Murder, She Wrote. In 1990, Cox co-starred as Los Angeles Police Chief Roger Kendrick in the short-lived
Cop Rock, presenting a striking physical resemblance to the real-world incumbent Chief
Daryl Gates. He also appeared as the antagonistic Mars Administrator Vilos Cohaagen in
Total Recall the same year. Cox had a guest role on
Star Trek: The Next Generation as Captain Edward Jellico in the two-part episode "
Chain of Command". He also played Henry Mason, the father of
Bree Van de Kamp (
Marcia Cross) on
Desperate Housewives. In 1997, Cox portrayed the fictional
President of the United States Jack Neil in the movie
Murder at 1600. Cox also portrayed
John Ramsey in the 2000 TV film
Perfect Murder, Perfect Town and
Senator/Vice President Robert Kinsey in
Stargate SG-1. Cox had a role in
The Starter Wife. He played Pappy McCallister, the husband of Molly Kagan's best friend Joan. He occasionally has done animation work, lending his voice to the Tyrusian deserter Doc in
Invasion America and Senator McMillan in ''
Todd McFarlane's Spawn''. Cox guest-starred in an episode of
Matthew Perry's 2011 series
Mr. Sunshine. Cox played Walter Kenney in
Dexter, season six, episode three ("Smokey and the Bandit"). His character was a serial killer known as "The Tooth Fairy", whom Dexter had idolized while growing up. He guest-starred in an episode of
Diagnosis Murder entitled "The Pressure to Murder", episode 9, season three. Cox played Gideon Claybourne on season 6 of
Nashville in 2018. Starting in 2022, Cox reprised his role as now-Admiral Edward Jellico in several episodes of
Star Trek: Prodigy. ==Music career==