Some critics have gone so far as to call The Wire, a drama about the Baltimore drug trade, the best television series ever.
But it is hard to imagine it finding a home on one of the traditional networks.
It is not just the gritty tone, or the graphic violence, but the ratings, which amount to only a few million viewers on a given week.
But for the last five years, The Wire has been a mainstay at HBO, the Time Warner-owned cable network.
This season, HBO tried something new in an effort to keep it foremost in the lives of its small, but devoted fanbase.
Since September, the network has put each episode of The Wire on its On-Demand service six days prior to its regular, Sunday night broadcast.
In its first week alone, the programme was viewed On Demand more than 188,000 times. By the fourth episode, that number had grown to more than 430,000, and helped to boost The Wire’s overall audience by 200,000 viewers from last season.
“We have always been about the quality of our work and the convenience of watching it,” said Chris Albrecht, the network’s chief executive. “In a world where kids are downloading Lost or whatever they want to download – that is the HBO model, and it has been for a long time.”
That strategy is helping HBO to its best year ever, with revenues already exceeding $3bn and profits expected to surpass $1bn. Its performance stands out at a time when much of the television industry is on edge.
Just last month, NBC Universal announced plans to fire about 700 workers in a cost-cutting exercise.
As shocking as the number was the acknowledgement from Jeff Zucker, chief executive of the NBC Universal Television Group, that the economic model that has sustained the major broadcast television networks for decades was under extreme pressure.
Traditionally, NBC and its peers have assembled mass audiences around a few big primetime hits and then sold those audiences to advertisers. The problem is that a proliferation of cable television channels, websites and videogames has fragmented their audience.
At the same time, new technology is allowing viewers to skip past commercials and to watch programmes when they please – often after time-sensitive promotions for film releases or department store sales have lost their relevance.
But HBO has so far proved immune to those forces. The reason is that it does not sell advertising but instead generates the bulk of its revenues from monthly subscription fees.
As a result, Mr Albrecht and his team do not sit up at night fretting about Nielsen ratings, or time-shifting. Rather, their obsession is churn, and whether customers feel that they are getting enough value from HBO when their cable bill arrives.
“I don’t even want people to think about disconnecting HBO,” said Dave Baldwin, executive vice president of programme planning. “I want that renewal to be automatic every month.”
That attitude has shaped the network’s programming strategy since it went on air in 1972, at the dawn of the cable business. In those early days, studio films and boxing lured paying subscribers.
In the 1990s, as the home video business began to emerge as a competitor, Jeff Bewkes, who is now Time Warner’s president and the presumed successor to chief executive Richard Parsons, changed course.
Under Mr Bewkes, HBO invested in a slate of original programming that yielded such critical and popular hits as Sex and the City, The Sopranos and Six Feet Under.
“The best advertisement for someone wanting to bring their show to HBO are the shows already on HBO,” Mr Albrecht said of the network’s creative success.
This year, though, there are whispers that HBO has lost its touch. After a nearly two-year hiatus, The Sopranos has been eclipsed by a group of Desperate Housewives, who now dominate the Sunday night ratings.
While a new generation of programmes has been well received, none has quite captured the zeitgeist like its predecessors.
But HBO executives insist that their network is often misunderstood.
It does not require a single, enormous hit to sustain it. Instead, HBO can succeed with a portfolio of niche programmes that attract loyal fans and, cumulatively, add up to a big subscriber base.
“In a world of more choices, it’s not likely that you’re going to be able to continue to drive mass audiences,” Mr Albrecht said.
“[But] for the 5m people who watch Entourage each week, it’s a homerun. The Wire is a huge homerun to Wire fans. That’s our business.”