There are many groups of inmates throughout the show and not everyone within each group survives the show's events. Oz chronicles McManus's attempts to keep control over the inmates of Em City. All plots, subplots and conflicts are given context and explanation by the show's wheelchair-using narrator, Augustus Hill. The show offers a no-holds-barred account of prison life.
Others, corrections officers and inmates alike, simply want to survive, some long enough to make parole and others even just to see the next day. Some fight for power - either over the drug trade or over other inmate factions and individuals. Under McManus and Warden Leo Glynn, all inmates in Em City struggle to fulfill their own needs.
Emerald City is an extremely controlled environment, with a carefully managed number of members of each racial and social group, with the hope of easing tensions among these various groups. In this experimental unit of the prison, unit manager Tim McManus emphasizes rehabilitation and learning responsibility during incarceration, rather than carrying out purely punitive measures. The majority of Oz's plot arcs are set in "Emerald City," also a concept from The Wizard of Oz.