Cyril's life continued to hang in a delicate balance as his execution loomed. Although his brother Ryan, Suzanne Fitzgerald and Sister Pete did all they could to fight the execution, no stay seemed to be forthcoming. While Sister Pete visited with him, Cyril ignored here and continued playing with his puppet 'Jericho'. She asked Cyril a question and he answered by calling her an expletive and grabbing her hand. Soon, Cyril began receiving electro shock treatment which keep him in a daze. Execution day arrived and just as Cyril's about to be strapped in, a stay was issued by the state. The relief is short lived when all other options are exhausted and the inevitable arrived. Cyril's execution is carried out while his brother Ryan weeps and prays and the inmates protest by beating on the glass of their pods.
Against his brother's wishes, Cyril participates in one of Sister Pete's interventions to make peace with Jia Kenmin, the asian inmate Cyril put into a coma last season. When new inmate Li Chien arrives, Jia Kenmin uses him as ploy to Ryan for revenge. When Ryan's attempt to shank Li is thwarted by Jia, Cyril picks up Ryan's shank and fatally Li. Although this was really an act to protect Ryan, Cyril gets sent to solitary to await trial for first degree murder. Once the trial starts, Cyril becomes agitated in the courtroom. Sister Pete gives him a hand puppet for him to talk to so he'll stay calm during the proceedings. The verdict comes down as guilty and Cyril's life is now threatened with execution.
Season 4 Part 2
Cyril's condition seemingly gets better, but just as it does, he beats a TV reporter badly, something Ryan tricks him to do. Cyril also gets into a fight with inmate Wick but only after Wick initiated the fight in the phone room. He participates in the experimental aging drug project with brother Ryan only Cyril begins aging and Ryan doesn't. After Wick dies, Cyril and all the other inmates are taken off the drug. Unfortunately, Cyril has one more violent outburst and he's transferred to death row where he meets inmate Stanton. When Ryan comes to visit, he finds Cyril talking with Stanton. Ryan, fearful of Cyril spilling details of his treachery, promptly tells Stanton to back off and not talk to Cyril.
Season 4 Part 1
Cyril begins with questions about Khan's death and these questions turn into violent nightmares. Sister Pete recommends that he and Ryan go to interaction with Dr. Gloria and her in-laws. At the first meeting, Cyril apologizes for killing Gloria's husband but the meeting ends in turmoil. Cyril's also placed on drug therapy to keep him calm, only it backfires when he's given too much by accident overdoses and falls unconscious.
Cyril starts this season by getting thrown in the hole for fighting with Schillinger. Ryan manages to get Cyril out and vows revenge on Vern. Soon Cyril gets drafted into boxing by his brother who sees money to be made. With Ryan training and slipping his opponents spiked water, Cyril rises to the top of the Oz boxing heap. For the boxing finals, Cyril has to beat Khan. Ryan arranges a "visit" by their father which angers Cyril. Cyril takes that anger out on Khan and fatally beats him.
Ryan's slow-witted brother comes to OZ for murdering Dr. Nathan's husband. He's put into Gen Pop and given Schillinger as a cellmate. Confused and unaware of any danger, Cyril is taken by Schillinger to a dark hallway and is raped by him. Ryan finds out, and stages a fight with Cyril so that he will be taken to solitary and away from Schillinger.