William Duke Mason

William Duke Mason is the main antagonist that appears in Criminal Minds together with partners Lester Turner in episode Outlaw in season eleven.

He was portrayed by Jesse Luken.

History
Mason was born on May 14, 1987, and was raised by his parents Jeff Koldyke and Violet Mason in Dallas in the Texas, his father left the family and Violet took him to Las Vegas in New Mexico, where he spent his first year in the middle school, his mother married another man, who was a drunk. Mason began to hate his way of life and soon began to interact in the wrong crowds. At school he became involved with a girl named Tammy Mae Vasquez. However, her relationship with her became increasingly tense due to her high risk lifestyle and her carefree friends.

At some point, he unknowingly had a son with Tammy whom she called Cole. Mason later dropped out of school and ran away from home, then met Benjamin Wade and adopted his lifestyle as a motorclycle rider, the two then committed crimes together, and a series of mass murders at a diner and traveled too Texas, where they stole a gas station in El Paso and then killed an official.

They were arrested by the police for trying to set fire to station. Wade was sentenced to long sentence while to Mason was sentenced to six years in prison for complicity, shortly after Mason would make friends with Lester Turner who was arrested for rape and assault in Lubbock, Mason saved Lester from being attacked by another inmate, and then they became close friends, with Mason neglecting Wade in favor of Turner, then a month later Turner and the two chose to commit crimes in the same area as when he was Mason and Wade before his arrest. All the while Mason would still be unaware of the existence of his son.

Outlaw
Mason and Turner commit a robbery at Dee's Original Diner, they steal the three officials and place them hostage and then kill them, then both arsonist the place together with the bodies killed by themselves. Then they both stay at the hotel and count the money. After Mason meets Tammy in a hotel, Tammy refuses to leave Mason and tells him to leave, Cole then appears and talks to his mother making Mason realize that he has a child. Tammy then orders Cole to leave and airms a shotgun by Mason, if he does not leave though he ends up going, then Turner tells Mason that he stole a phamacy by shaking Mason and making them go away with his bikes.

They then stop at a gas station, and Mason buys food in a store, when he recognizes him and catches a shotgun at the threatening him, Mason tries to calm him down as he picks up a phone and tries to call police but he is killed by Lester, and Mason shoots the camera, when Mason sees the boy and the father he points the gun more hesitates to do it, then Mason and Turner have a fight and Mason goes away.

Mason then returns to Tammy's house, but finds Cole alone at home with his nanny Ruth. He takes Ruth hostage and starts playing with Cole, Tammy returns home and sees Mason, she tries to make Cole go to her, but Mason refuses to let him it, and keeps playing with Cole, promising Tammy that he will make up with her, after that Mason forces Cole and Tammy to get in the car and he leaves Ruth behind. After that Mason demands to know if Cole is really his son that Tammy confirms, and realizes that Mason was behind the murders in 2009 and the wave of crimes. After Turner appears and insults Mason introduces himself to Tammy with Mason's partner, Mason tells Turner to retreat with the arrival of BAU and with the appearance of the police, both Mason and Turner decide to make a truce and shoot the police because the two refusing to be arrested, Lester is later shot dead, Mason sees Tammy and Cole being dragged by the police, and realizing that not being part of Cole, Mason starts firing until he is shot dead by Raul Montoya.