As a writer and executive producer for seven seasons of TV's superb Homicide: Life On The Streets, Tom Fontana helped transform the moribund cop-show genre, with its formulaic car chases and Dragnet-style insta-justice, into something much closer to the everyday. Though Fontana and company pushed the boundaries of network television with vérité camerawork and realistic language and violence, Homicide benefited in part from its constraints: With limits on gratuitousness, the show could focus more intently on the existential crises of professionals who shared an unusual intimacy with death. After years of self-censorship, both with Homicide and earlier as a writer for St. Elsewhere, Fontana finally allowed his id to run amok in the HBO series Oz, unburdened by the rigors of nervous executives, skittish advertisers, and, in many respects, good taste. In detailing the Machiavellian goings-on in a maximum-security prison, Fontana puts the American melting pot itself on the burners, as representatives of every class, ethnic group, and religious background scrap for power over limited territory. Since many are long-term inmates or lifers, they have fewer incentives than usual to abide by the rules of polite society, adding to a pressure-cooker atmosphere that constantly threatens to blow the lid off civilization. To his credit, Fontana goes all the way with this concept, pitting one group against another in a bloody, inexorable descent into chaos. The governor battles prison administrators, who in turn contend with the corrupt guards aiding the drug traffic, which is hotly contested by the African-American, Latino, Italian, Aryan, and Muslim prisoners, all of whom are ensnared in an endless cycle of violence. In Oz, Homicide's sobering realism has been replaced by melodrama so extreme and explicit that Oswald State Penitentiary seems less like a prison than a laboratory experiment testing the limits of human misbehavior. Under the microscope, Fontana looks at Emerald City, an innovative cellblock with clear glass walls designed to encourage a greater sense of safety and intimacy among the inmates. Dreamed up by Terry Kinney, an idealistic administrator who favors rehabilitation over retribution, the fishbowl concept quickly goes awry when escalating tensions become impossible to contain in such a small space. Exacerbated by the governor's new "No Perks For Prisoners" program—which bans cigarettes and conjugal visits, and reinstates the death penalty—feuds over the drug trade and related blood wars lead to a rash of murders and the threat of a full-scale riot. Among the major players are Lee Turgesen, a former upper-middle-class lawyer who becomes easy prey for a white supremacist (J.K. Simmons); Tony Musante, an aging mob boss who controls most of the drug traffic; Dean Winters, the young schemer behind most of the killings; and Eamonn Walker, a principled Muslim imam who prepares his followers for an uprising. Almost every episode in Oz's first season centers on a capital-T Theme (God, sex, the death penalty, addiction, health), which is key to a larger problem with the series. While Fontana's brilliance as a dramatist has never been clearer, he doesn't trust his ideas to rise naturally from the material, so he drives them home for good measure. His dense plotting and richly drawn characters cover every aspect of prison life with palpable intensity and detail, yet he still feels the need to return to the faux-poetic sermonizing of a streetwise narrator (Harold Perrineau), who speaks to the camera from a rotating glass cage. But Fontana's weakness for bad performance art cannot be separated from his passion for challenging, original television that takes full advantage of the medium and ventures boldly into combustible territory. As proof of his scary dedication, Fontana admits in the commentary track of the new DVD set that he offered up his own shoulder for the Oz tattoo emblazoned on the opening titles. For better and for worse, the series bears his unmistakable imprint.