The critically acclaimed, award-winning prison drama about life - and sudden death - in an experimental prison unit nicknamed Emerald City.

The unit's name derives from the glass cells of the prison-within-a-prison. This is home to some of the most violent men on television - and a far cry from the Technicolor vision of MGM's classic 'Wizard of Oz'.

The stars of this brutal world are the inmates, the murderers, drug addicts and violent gang-members, and their guards, the people who keep them imprisoned and who try to stop them from killing each other on a daily basis.

They don't always succeed…