Mason is a notorious black hat hacker. In the past he has hacked both the Pentagon and the NSA. The CIA computer guys call him the Kobayashi Maru which is a reference to an unbeatable exercise in Star Trek.
He was recruited by Marcus Starke to steal a valuable WWII Painting. After Starke's crew's job intersects with Nathan Ford's team he spars with Alec Hardison with both using their hacker skills to stymie the other with Chaos briefly gaining the upper hand. Later it was revealed he attempted to eliminate Sophie Devereaux by planting a bomb in a bouquet of flowers due to Sophie's notorious reputation, and eliminate Starke with a car bomb.
He was seen attempting to leave the country, to Paris, but was stopped by airport security who found stolen paintings (planted by Hardison) in his luggage. He was arrested, and incarcerated to federal prison, but escaped sometime in 2010.
By Season 3, Mason has moved from being a hacker to mastermind and organizer of his own crew (much like Marcus Starke's Crew, it is more like a "wiz mob"). In which he used Evan Dooley Jr. as a lure for Leverage Consulting & Associates to come in, and allow Chaos to initiate the greater part of his plan. He was arrested by the FBI, but later escaped or was freed.
He returned in The Last Dam Job, where the marks were ready for Hardison's hacking techniques. Mason was deliberately hired by the Leverage team because the history of mistrust between him and them. He didn't get along with Archie Leach, Eliot Spencer or Hardison.
He has a crush on Parker. In The Ho Ho Ho Job he makes suggestive comments about how "yummy" she looked in her elf costume. In the Last Dam Job he again hits on her in front of Hardison and her father figure Archie Leach.
- Is an amazing hacker 2nd only to Hardison
- Mastermind (As of "The Ho Ho Ho Job")
- Remote Van
- Runs a similar van to the one Hardison uses.
- Drinks Squeeze Cherry Soda, which is similar to Hardison's Squeeze Orange Soda.
- Considers Sophie one of the best con artists.