Top Boy, Channel 4

One striking fact about Ronan Bennett's punishing four-part East End gang drama is that, so far, there hasn't been any sign of a policeman. No scruffy, down-at-heel detective with a chip on his shoulder, no thuggish Flying Squad heavies, and certainly no Wagner-loving aesthete who goes around quoting Elizabeth Barrett Browning.

Instead, Top Boy exists exclusively in its own sealed environment of violence, fear and dog-eat-dog ambition, where being sucked into gangland drug-dealing is the only option that bears any resemblance to a career ladder. Let's face it, how many kids can hope to get trials with West Ham United? As chief protagonist and aspiring dope potentate Dushane (a superb Ashley Walters) puts it: "I haven't anything to be except this." In the mostly black families living on high-rise housing estates, from where they can see the fat-cat towers of Canary Wharf sticking up like raised digits in the distance, the cycle of single mothers and children casually abandoned by their fathers is the anti-gift that keeps on taking, creating a demoralising vortex of welfare dependency and seething frustration.

But Bennett's feat is that he hasn't written Top Boy as a liberal cri de cœur or a Hackney social workers' manifesto. He has simply depicted a hideously believable environment and peopled it with brutally plausible characters, to the point where you could cry at the realisation that chunks of our dilapidated nation really look like this. Inventive colour grading and Brian Eno's coolly evocative music lend the project a cinematic weight.

At first I didn't think I was going to get on with it very well, since I couldn't understand anything anybody was saying for the first 15 minutes. Not only was all the dialogue delivered in gangsta/jafaican/ghetto/whatever, the sound also seemed to have been deliberately mixed into a sub-audible murk. The cavalry arrived in the heavily pregnant shape of Romford's finest, Kierston Wareing (pictured above with Malcolm Kamulete) as Heather, holding forth in strident Essex Girl as she embarked on a path of (she hoped) life-changing crime by nurturing a flat full of marijuana plants. This was at the behest of an insistent Vietnamese gentleman who promised her "very good price" for her leafy crop.