Season Four premiere. The world of Oz--an experimental prison within a prison known as the Emerald City--reopens its doors with the inmates still on a 24-hour lockdown an ...

The African-American inmates point the finger at McManus for letting Em City get out of hand. After that and his recent erratic behavior, McManus gets the ax from Glynn. ...

Glynn learns from Adebisi that he was given the gun by former C.O. Hughes. Morales enlists Rebadow's help in taking Hernandez's place in the drug ring run by Adebisi and ...

Em City gets a new Unit Manager, Martin Querns, whose methods are hardly orthodox. Beecher's torment over his missing children is worsened when Schillinger presents him w ...

As Querns implements his new course of action, the dynamics of Em City start to change, causing friction with Officer Murphy. Beecher falls deeper into depression as he w ...

In an effort to reduce violence, white inmates are transferred out of Em City. Said and Arif talk to Querns about the negative impact of his changes, but their efforts ar ...

With things wild in Em City, O'Reily begins a surprising affair. Zabitz asks Schillinger for protection from Keller--who tries to get into the rehab program to make amend ...

After Hughes' attack on Devlin, Glynn withdraws from the race. Miguel Alvarez is still on the loose. Supreme Allah receives an unwanted surprise. Hill pays big time when ...

Six months have passed. Said was acquitted of Adebisi's murder on grounds of self-defense. Up Your Ante, a game show, has joined Miss Sally in the prisoner's TV lineup. M ...

New inmate Burr Reading arrives, ready to take charge of the African-American drug scene. Dr. Nathan returns to Em City, and finds the biggest adjustment is dealing with ...

Morales looks to pit the Chinese against Redding. Alvarez offers Glynn his services as an informant as a way out of solitary. Dr. Nathan announces that Em City inmates wi ...

O'Reily regrets getting Cyril involved with the trial drug when it starts taking effect. Meanwhile, Giles' request for an unusual execution creates controversy and the Ch ...

O'Reily is in for a surprise when a visitor reveals the truth about his past, while Cyril faces trouble for his difficult behavior. Meanwhile, Morales and Redding lay out ...

McManus calls a superficial truce between Redding and Morales. Basil finally sees his wife, but Hughes ends up spoiling their happiness. Meanwhile, Cyril's latest outburs ...

McManus can't turn his back on White. Beecher tells the parents of the girl he killed that he's up for parole. Howell tries to blackmail O'Reily so she can get to Cyril, ...

In the Season Four finale, Hill discovers where his true allegiances lie in Oz. Redding's plot to use the Colonel against Morales has an unexpected outcome. Beecher's ago ...