Snow is falling on the Jockey pub, which is decorated with gaudy Christmas lights. One lad is chasing another, who's just nicked his bike. "Use it or lose it, arsehole," jeers the thief as he speeds past a snowdrift piled up outside the pub door.
The camera zooms in on the snowy mound, and slowly a large patch of it turns a shade of yellow. The drift starts to rise, revealing a truly scary, snow-clad figure. No, it's not the Abominable Snowman - it's something even more frightening: Frank Gallagher stirring from his alcohol-induced coma after a particularly heavy session at the Jockey.
Frank tries to brush himself down, but his efforts are hampered by the can of lager apparently welded to his hand. As he prepares to stagger off home to pretend to his partner that he's been mugged, it dawns on Frank where he is. He mutters: "I didn't think we had a white duvet." Just another night on the Chatsworth estate, then.
Frank is the nominal head of the Gallaghers, the family at the centre of the TV hit Shameless, and the bunch who put the fun into dysfunctional. Channel 4's series is an absorbing comic portrait of a family surviving - indeed, flourishing - against all odds on the sort of sink estate routinely written off as beyond help.
The feckless Frank (David Threlfall) has moved in with his agoraphobic neighbour. In his absence, the family is run by the super-capable 20-year-old Fiona (Anne-Marie Duff) and her amiable car-thief boyfriend Steve (James McAvoy).
I'm on the set of Shameless on a bleak Manchester industrial estate. It's a suitably depressing backlot, strewn with the detritus of every rundown council estate in the country; old cookers, broken chairs, soggy carpets, dirty orange traffic cones, wrecked trellises, nettles and odd tyres. In the middle stands an ancient, dilapidated green and white camper van.
This is a world where everyone exists on the margins, ducking and diving to make ends meet. Frank's dream is to discover a dead person whose identity he can steal and whose benefits he can claim. His oldest son, Lip (Jody Latham), makes a living out of fraudulent insurance claims. In Channel 4's Christmas special, Lip gets hold of some condemned meat. When he sells it down the Jockey, the entire estate gets food poisoning and the Chatsworth is sealed off by the military.
When the first series was screened in January, Paul Abbott's drama was lauded by critics. It picked up several awards, including the Prix Italia for best drama series. On BBC2's Newsnight Review, Natasha Walter said: "I love the buoyancy of it, the fact that it is written from the heart. It feels so rare to see something on television that has come from one person's heart rather than having passed through executive feelings about what would do well with the audience. It feels real, alive."
The Daily Telegraph wrote: "Shameless thrives because it makes you care so passionately about the characters [Abbott] presents in all their messy, fully-lived detail." The Scotsman compared it with Alan Bleasdale's 1982 vision of Thatcher's Britain, Boys from the Blackstuff: "Shameless might just be strong enough not to be embarrassed to be mentioned in the same breath."
The series has turned many of the cast into stars. Threlfall, in particular, has been catapulted into the major leagues by his pyrotechnic performance as a man equally hooked on booze and benefits.
But even he has been taken aback by people's reaction to the show. "It's brilliant to be in something that people are mad for," he says, beaming. "As a sign of how much they're enjoying it, people have started to shout abusive things at me in the street, like 'Frank, you pisshead.' It's like something from Spinal Tap, which can only be a good thing."
What is it that makes Shameless so special? First, it is authentic. The show may feel heightened, almost cartoon-ish, but it is grounded in reality - which is no surprise when you learn that Abbott based great swathes of it on his own experience of growing up on one of the toughest estates in the north-west of England. He has followed Gustav Flaubert's injunction to young authors: write what you know.
Abbott's life story is worth recounting. One of eight children, he was forced to learn to live on his wits when his mother abandoned the family when he was just nine years old. Things got worse when his father left home two years later.
The riotous assembly of children were left in the care of their 16-year-old sister, who just happened to be pregnant. Their council house had no bathroom, and the clan lived in a state of semi-anarchy, constantly fighting and getting into trouble with the police. All of them were sexually active by the age of 13. It all became too much for Abbott, who had to be sectioned after a nervous breakdown at 15.
It sounds intolerably chaotic, but Abbott has no complaints. He's still extremely close to his siblings, and reckons that a third of his income now goes on helping them: "I'd do anything for them."
At the time, he had no idea just how harsh his childhood was. "When I reached the age of 25, I thought, 'Jesus, that was tough.' But when you're inside it, you're not aware of it because you don't know that life could be any better. There was tons of scrapping, but because it happened all the time, it was no big deal and you were immune to it."
Having slipped underneath the radar of social services, all the children acquired masters degrees in street wisdom, in record time. "The deserting parents, the teenage pregnancies, the lack of legitimate income, the criminal sentences - we got wise to the fact that shit happens," Abbott says. "Chaos became the norm, and our threshold for tolerating upheaval was tested to the limit.
"From this accelerated growth spurt came the rewards of accelerated life skills: we could all cook, clean, decorate a room at three in the morning, strip a bike - someone else's! - down to its basic components without leaving forensic traces. The ones who hadn't got pregnant or got anyone else pregnant knew more about contraception than we needed to."
But some of it, Abbott looks back fondly, was an absolute blast. "Bits of that life were unmissable. Imagine a teenage party where your parents clear out to * * give you the run of the house - but for six years! The lack of constraints could often be stimulating. I remember us once spending half our household budget on all the top 10 singles that week - just so we could open the windows, whack up the volume and make the street think we were loaded. What parent would have countenanced that?"
And those experiences, indelibly seared into Abbott's memory, continue to have benefits: "I look back and I realise that that kind of life has made me the writer I am today." Indeed, fiction was in many ways his salvation. "I started writing when I was 14 - which in our family was like being caught masturbating,"Abbott laughs. "But for me, it was a way of talking without being contradicted. In all that racket, I could say what I wanted."
Abbott has spent the last seven years putting his childhood through his artistic filter, but it was worth it because what came out was Shameless. George Faber, the executive producer of the series, says: "It's characteristic of Paul's originality that he has taken his troubled, poverty-stricken past and created an engaging, life-affirming and comedic world. He's pulled off the trick of making you wish you'd had an upbringing like this too." The writer attests that "the warmth and the humour in Shameless are not fake".
But what do Abbott's family make of their fictional counterparts? He says: "They're fine about it. There are no direct portrayals. Frank is not based on my dad. I've made him a mixture of people. I actually know five different Franks, people who have become astonishingly adept at lying to themselves. They're the type of blokes who'll see children asleep on a pile of coats at a wedding and go 'Aaah!', and you want to say to them, 'What on earth did you ever do for your own children?' But those people must have a brilliant life because they believe everything they say. I'm totally envious of them."
If you can believe it, Shameless is actually a watered-down version of reality. The writer smiles that "real life was actually more extreme. There are some things that just can't appear in a drama."
And there have been caveats amid the critical praise. In The Daily Telegraph last week, the paper's former editor Charles Moore castigated Abbott for vulgarity: "As I write, I am looking at a Christmas brochure for Channel 4. It contains an interview with Paul Abbott, author of the 'current hit show, Shameless'. Clever Paul swears a lot, and proudly tells a story about how, when his brothers held him upside down to help him steal a Christmas tree from his Yugoslav next-door neighbour, he was so frightened that he started urinating. Ha ha."
For those involved in Shameless, however, its full-frontal flouting of the tenets of taste is an essential part of its attraction. "Paul is defiantly anti-PC," says Anne-Marie Duff. "But artists shouldn't conform. It goes against the conventional recipe for success to have a series full of dislikable, manipulative and dysfunctional characters, but Shameless works so well because of the conviction with which Paul tells these people's stories."
Abbott stresses that the series would present a far less rounded portrait of the Gallaghers if it had to remain strictly within the boundaries of good taste. After all, it is called Shameless. "Normally you dream up something and then think, 'No, you can't get away with that,' but in Shameless you can. In the last series, we had underage sex and drugs and saw Frank nut his 15-year-old gay son.
"I even took the piss out of the mob that hounds paedophiles. I based that on the [James] Bulger trial, when people bayed for the blood of two 10-year-olds. I wasn't worried about offending people. It's a tricky subject, but that's why you should write about it. People really engaged with that episode. They got it."
The writer, who is married with two young children, goes on to stress that "I have not yet found the point where I'd draw the line. In this series, Frank is continually trying to kill his dog. He throws it into the canal, but it keeps coming back to its master. You even see Frank throwing a tennis ball for the dog to chase on the M62. The dog comes back covered in debris from a car crash.
"I'll get complaints about that scene, but I know how to defend it. It's just that Frank doesn't want to pay all that money for dog food. It's such fun to play with that sort of outrageous behaviour."
Abbott even argues that the Gallaghers are essentially a lovable clan. "They're very like the Waltons," he says mischievously. "They teach us things - but in a more extreme way. When viewers see the Gallaghers fighting with such ferocity to remain a unit, they respond to it.
"If you immerse yourself in the family and write from an internal perspective, however repulsive they might look from the outside, you can make people warm to them. Even when they lie, cheat and steal, you can make them appear lovable if you show that this behaviour is imperative for their very survival. I see Shameless as a subversive soap."
Duff agrees. "As mad and as challenging as this series is, it has a good heart. So much that is going on in the world is scary and serious, so it's refreshing to have something like Shameless that is utter escapism. People have loved being able to lose themselves in it."
The other criticism is that the show patronises society's dispossessed. The makers strongly refute this, contending that it paints an honest picture of an urban underclass. James McAvoy, who also starred in Abbott's State of Play, says: "TV drama recently has presented us with a lot of idealised middle-class lives, which many viewers can only aspire to. The working class is only ever portrayed as in turmoil. While not ignoring the realities of life on estates like the Chatsworth, Shameless offers a beautiful portrait of working-class life. People can identify with the Gallaghers, and take something positive from them.
"While it's completely valid to have a stereotypical drama about the dour North, it is also completely valid to give another viewpoint. There are people out there just like the Gallaghers. Shameless is not taking the mickey out of them. It is celebrating them," McAvoy says.
Shameless was a risky idea. Abbott is the first to acknowledge that it could easily have been crass and offensive. "It could have turned out like a rude, cheap soap," he concedes. "I was surprised by the way people embraced it. I think it struck a chord because it didn't look like any other kind of TV they had seen before. Viewers celebrated the fact that it went out of its way to be different.
"Most TV drama lacks ambition and is too timid. But Shameless is bold. It's telling a story in an exuberant way about a subject that could otherwise have been quite grim. It's exposing the public to a section of society that hasn't ever been popular before."
The first series netted an impressive average of 2.6 million viewers. An American version is being planned, to be made by John Wells, the producer of ER and The West Wing. Abbott is confident that the strengths of Shameless won't be diluted for the US market.
Earlier this year, Bafta announced that Abbott, 44, had won the Dennis Potter award for outstanding writing in television. Off the back of such successes as State of Play, Cracker, Clocking Off, Reckless, Linda Green and Touching Evil, he is the most in-demand writer currently working in television.
A wiry ball of energy on set, Abbott seems a driven character, fizzing with new ideas. Friends describe him as "a force of nature", and his formidable energy shows no sign of waning. He's working on new series of State of Play and Shameless, as well as executive producing pieces by Richard Curtis, Lucy Gannon and Tony Grounds. He's clearly a man who doesn't need much sleep.
Perhaps Paul Abbott's scripts have chimed so resoundingly with viewers because he puts so much of himself into them. "Most writers haven't realised that you've got to give a bit of yourself away to be successful," he says. "I learnt that on Cracker. You have put yourself into a drama to make it worthwhile, otherwise it's just not satisfying. If you have fears in life, confront them in your writing. Is this sort of work emotionally draining? No; I find it cathartic - and so cheap."
What does Abbott mean by that? "Instead of paying a shrink £200 an hour, you get to pour out your emotions and sell them for thousands of pounds."
'Shameless Christmas Special' is on Channel 4 at 9pm on 23 December. The new series begins on 4 JanuaryReuse content