Perhaps best known for his role in World Championship Wrestling (WCW) as "The Taskmaster" and his leading of the "Dungeon of Doom".Sullivan wrestled as "Johnny West" in the NWA (Gulf Coast) in the early '70's, capturing the NWA Gulf Coast Tag Team championship (along with Ken Lucas), defeating Jack Morrell & Eddie Sullivan on March 11, 1971. Next, he went to NWA Florida Championship Wrestling in 1972 and captured the tag team championship with Mike Graham. He took three years off from the NWA to join the WWWF as a mid-card face (from 1974–1977). Had a (rare for the time) face versus face battle with Pete Sanchez on an MSG undercard. Sullivan also wrestled as a face for Roy Shire for the National Wrestling Alliance in their San Francisco territory. Sullivan then worked in NWA Georgia Championship Wrestling and Florida Championship Wrestling as a face until the early 1980s. His first heel run was in Memphis where alongside Wayne Ferris (The Honky Tonk Man) and manager Jimmy Hart he battled the local faces including Jerry Lawler. He left Memphis for Georgia but once again turned heel while in the Georgia territory before he moved on to Florida to work for Eddie Graham.
Known as the heel "Boston Battler", Sullivan's "devil worshiping" gimmick started during this time. In CWFL he became associated with "Maniac" Mark Lewin (Purple Haze), Bob Roop, The Lock and Luna Vachon amongst others. Sullivan split his time with the ICW and brought the devil-worshiping gimmick there, along with Lewin and Roop. He had the Fallen Angel as his valet, who later became known as Woman. Sullivan was the top heel in ICW when the company first went national and had noted feuds with Austin Idol, Superstar Billy Graham, Bruiser Brody, Joe Savoldi and Blackjack Mulligan.
In 2003, Sullivan made one surprise appearance in Total Nonstop Action Wrestling, as the officiator in the first Clockwork Orange House of Fun match. In late 2003/2004, he worked for the All World Wrestling League/Big Time Wrestling. He currently competes in the Pacific Northwest with his nephews.( D.V. AND R.R) they won the Allied Independent Wrestling Federations World Six Man Championships March 24, 2012 in Poulsbo, Washington.
On April 28, 2012 Sullivan made a surprise appearance, initially under a mask, during the Shane Douglas vs. 2 Cold Scorpio match at Extreme Reunion in Philadelphia, PAIn an example of kayfabe (the storylines in wrestling) becoming real, Sullivan's wife Nancy Daus, left him in favor of his rival, Chris Benoit. In the late 90's Sullivan conceived an angle where Woman (Nancy Daus Sullivan, Sullivan's wife both on-screen and off), would leave his character for Chris Benoit's. Sullivan insisted that the two should travel together to preserve kayfabe for the general public and to make the affair look real, (hold hands in public, share hotel rooms, etc.). Nancy ultimately married Benoit in 2000. Because of the real life imitating kayfabe, Sullivan and Benoit had a contentious backstage relationship at best and Benoit defeated Sullivan in a Retirement match at Bash at the Beach. Benoit did, however, admit having a certain amount of respect for Sullivan, saying on the DVD Hard Knocks: The Chris Benoit Story that Sullivan never took undue liberties in the ring during their feud, even though he blamed Benoit for breaking up his marriage.