Complete fourth season of the seriously grim and gritty prison drama. As the season begins, the lockdown ends. Khan's body has been taken off life support and the Muslims choose Arif (Granville Adams) to lead them. Meanwhile, Cyril's (Scott William Winters) having nightmares about delivering the fatal blow to Khan (Ernie Hudson Jr) in the boxing match. Ryan (Dean Winters) asks Sister Pete (Rita Moreno) to intervene. Murphy (Robert Clohessy) makes a suggestion to help ease some of the strain in solitary after another inmate commits suicide. Father Mukada (B.D. Wong) plants an inventive idea in Beecher's (Lee Tergesen) head on how to deal with Schillinger (J.K. Simmons). Shirley Bellinger (Kathryn Erbe) returns to await her date with the noose. New inmate Mobay (Lance Reddick) arrives to Oz and his cellmate Hill (Harold Perrineau Jr) is immediately suspicious. Gov. Devlin (Zeljko Ivanek) invites Glynn (Ernie Hudson) to be his running mate in his re-election bid, and McManus (Terry Kinney) gets an update on Wittlesey (Edie Falco), who hasn't returned from vacation. Episodes comprise: 'A Cock and Balls Story', 'Obituaries', 'Bill of Wrongs', 'Works of Mercy', 'Gray Matter', 'A Word to the Wise', 'A Town Without Pity', 'You Bet Your Life', 'Medium Rare', 'Conversions', 'Revenge is Sweet', 'Cuts Like a Knife', 'Blizzard of '01', 'Orpheus Descending', 'Even the Score' and 'Famous Last Words'.