How far would you go to survive? Would you lie? Steal? Sell drugs? Would you give a blowjob to a man you despised? Could you murder a man you didn’t even know to prevent another from murdering you? Is saving your life worth spending the remainder of it in a 9X6 cell with no windows and virtually no human contact?

If not, you wouldn’t last a day in the Oswald State Correctional Facility, known among its inmates as “Oz.” It’s also the fictional site of HBO’s longest running dramatic series, Oz (now in its sixth and final season), and one of television’s most explicitly violent and sexual programs.

But as any long-term viewer can attest, Oz is not about sex and violence. It is about betrayal, brotherhood, fear, frustration, redemption, and retribution. It’s also about death. Over the first five seasons, some 50 characters have died, most horrifically. (Executive Producer Tom Fontana jokes that he is ending the series this year because he has run out of ways to kill people.) Other characters have been crippled, branded, maimed, blinded, and tortured. Many of the inmates have been outright raped; others have “willingly” engaged in sexual acts to appease those in power — guards as well as prisoners.

As the series comes to its end, some viewers may be wondering whether the writing staff will forgo the sex and violence for resolution and redemption. The answer is, so far, no. Fontana originally planned to end the series two years ago when he lost his lease on the studio where Oz was filmed. His first idea involved an explosion that partially destroyed the prison, a plot device that eventually became the cliffhanger for season four, as a new studio was found and the series was revived.

Now, it appears that Oz will end much as it began — in the middle. In the first three episodes of this season, the series has provided no hint of an overarching resolution. New issues, characters, and storylines have been introduced — and the series is known for carrying plotlines not just through multiple episodes, but over years.

So, the question becomes not what so much what will happen, but how will Oz be remembered? For one thing, it has raised timely and timeless sociological questions in a format that crosses freely from realism to the surreal. Certainly, Oz is not the first tv series to show life in prison, and numerous films have been set inside U.S. correctional units. However, no other fiction show has offered such a frighteningly realistic look inside our nation’s prisons or so openly debated their moral and social obligations.

While the majority of us will never experience the terror of prison, we all live in a society riddled with crime. Many debates have centered on what role our penal system plays — in stopping or perpetuating it. What are prisons’ responsibilities? To punish lawbreakers? To lock up “undesirable elements”? To rehabilitate offenders? And how might any of these goals be achieved?

Oz examines this difficult dilemma by juxtaposing two sections of the prison. “Emerald City” is an experimental unit that provides prisoners with alternatives to sitting in small cells all day. They have access to educational programs, sporting contests, and artistic endeavors. In contrast to Emerald City is Gen Pop (general population), which is more like a traditional prison environment, with few options provided to keep prisoners out of trouble.

In addition to exploring the question of which environment best serves the needs of inmates, the series raises current moral, political, and legal issues: should we execute the mentally ill or retarded? What role can religion or psychiatry play in helping prisoners find “the right path”? Is it fair to ask prisoners to serve as human guinea pigs for medical experiments? Can and should businesses operate out of prisons with inmates serving as cheap labor? And, at what point does punishment become inhumane?

To frame such complex matters, the show offers narrator/inmate Augustus Hill (Harold Perrineau). Though he was killed at the end of last season, Hill has continued to narrate, though now he shares that responsibility with other dead inmates. Each narrator highlights a particular, though broad, theme for each show — God, Death, Communication, etc. — quoting philosophers, poets, politicians, songs, and movies. The dead inmates walk among and talk to the living, although the living remain unresponsive. The prison has become a disco, a cemetery, a war zone, among other things, as the narrator elucidates that week’s theme. Often, startling images and photographs flash behind the narrator as he or she speaks. One narrator this season didn’t speak at all, but sat and played the cello as Hill spoke.

As this innovative approach to storytelling suggests, Oz‘s greatest strength is its consistently excellent writing. Head writer Bradford Winters (whose brothers, Dean and Scott, play inmates Ryan and Cyrill O’Reilly) drafts gripping storylines that revolve around a diverse cast of compelling characters. Oz has been accused by one reviewer of being “Melrose Prison,” due to the fact that characters are continually shifting their alliances, in much the same manner that soap opera characters are perpetually switching romantic attachments.

However, as one former prison inmate and fellow Oz fan told me, “That’s what it’s like, man. Just like that. Only it doesn’t all happen that fast.” He insists that what is heard in Oz is what can be heard in any prison, and that the alliances that rule Oswald — the Aryan brotherhood, the Latinos, the Blacks, the Italians, the Muslims — are found in most prisons in this country.

The show’s other, less realistic, aspects are equally worthy. Other series have been surreal (Twin Peaks, Dr. Who), while others have debated current issues (The West Wing, the Law & Orders). But Oz distinguishes itself through its innovative structures, images, and language. Imaginary sequences don’t so much propel plot or develop characters as they explore themes. And most often, these themes — whether broad (death) or specific (sexual abuse by the clergy) — cannot be resolved.

Many issue-oriented series come with soapboxes, on which characters stand to tell us what to think. Oz lays out an issue and opposing viewpoints, then leaves us to decide. This is not to suggest that the series does not provide any resolution to its storylines. However, these are difficult, messy, and often contrary to what viewers may have wanted to see.

Some might argue that Oz‘s greatest contribution is that it opened the door for other explicitly violent or sexual programs, such as The Sopranos and Queer as Folk. But Oz‘s distinctive storytelling has been more acutely groundbreaking. Viewers can consider themselves blessed to have had six years inside Oz.