He is played by the Scottish actor Peter Capaldi, who has hitherto always been a rather homely sort of thesp. You always knew where you stood with Capaldi, a man who exuded an air of scholarly erudition in a succession of solid TV melodramas, some of them starring Robson Green. Not any more, though. As Tucker, I tell him, he is absolutely terrifying.
"Well, that's very nice of you to say, thank you," he says. " I certainly find it terrifying to play him. Exhausting, too. He does shout rather a lot."
The Thick Of It, which co-stars the sublime Chris Langham as an inconsequential minister who wants to be so much more and spends a lot of his day-to-day existence being heckled by the vulpine Tucker, was created by Armando Ianucci, the writer-director behind The Day Today and I'm Alan Partridge.
The first series was screened earlier this year on BBC4 to great acclaim, and with good reason: this was possibly the funniest, and certainly the most savage, British satire since The Office. The second series starts this week (both will arrive on BBC2 soon), and the good news is that Tucker - Alastair Campbell by any other name, surely? - is as apoplectic as ever.
"We had a screening at Westminster recently which was enormous fun," Capaldi says. "It was attended mostly by low-flying MPs, their press people and staff, and that was fascinating for us because we began to realise that these were precisely the kind of people we were portraying."
These "low-flying MPs" then informed the cast that they had created an incredibly accurate portrayal of government life, not least in its creative use of every expletive under the sun. Within Parliament, apparently, the f-word is not just a verb, but noun, adjective and past participle too - sometimes simultaneously. Likewise, the multiple b-words, the naughty s-ones and, of course, the most hallowed of all, that one beginning with "c".
"Swearing is effectively their only means of communication, so we were told," he says. "So, yes, these MPs loved it. They loved the fact that they were being satirised on television. But that's unsurprising really, given the level of ego in politics."
Has he had any direct response from Alastair Campbell yet? After all, the entire show is a homage, of sorts, to the Prime Minister's former right-hand man, no? Capaldi receives this question with a cool and mischievous smile. He brings his coffee cup to his lips and sips, but only once he has swallowed does he make eye contact. "I'm sure..." he begins, carefully, "... I'm sure that Alastair considers himself far more charming than Tucker, and of course he is - but that's not to say he is based on him, because he isn't, not at all. Anyway, I've not received any feedback."
The smile becomes a smirk; pronounced crow's-feet lend his watery eyes a sardonic glint. "I think," he begins, and then he promptly reconsiders. "Actually, no, I don't. It's rather difficult to comment on, really." And so he doesn't and we move on.
Peter Capaldi was born in 1958 into a café-running Italian family in Glasgow. The man who would one day collect an Oscar (about which more later) harboured dreams about becoming an actor, but when he failed to get into drama college, enrolled at art school. Briefly, he became a guitarist in a punk act with the hopelessly New Romantic name of The Dreamboys, and as he was graduating, the Scottish director Bill Forsyth cast him alongside Burt Lancaster in the film Local Hero. He was 23.
"It was a pretty terrific start to my career," he says, "but also a rather misleading one. I didn't have a clue what I was doing, and I had no idea what to do once the film had finished. I had no agent, no experience, and I was really very gauche."
After frittering away much of the money he'd earned from the film on beer and curry, he headed for London, still clueless, where his fellow Scottish actor Dennis Lawson, Ewan McGregor's uncle, helped him get theatre auditions. By the mid-1980s, he was a jobbing actor and renting a room from the journalist John Preston (now the television critic for The Sunday Telegraph), who was trying to write a screenplay and needed Capaldi's help in giving his Scottish characters an authentic voice.
"I ended up getting completely immersed in it," he says, " although, if I'm entirely honest, I hated it. I find writing very difficult indeed, and although I've done a fair amount of it ever since, I never quite made the discovery that I was particularly good at it. What I did realise was that I could finish a script and rewrite it endlessly and that, by a war of attrition, I could eventually make something workable from it. And that, I discovered, was effectively the currency by which this whole business works: generating material. Without it, there's very little work."
He set about writing his first film (which would eventually become 1992's Soft Top, Hard Shoulder) and then tried his hand at a short film, which he was able to write and direct himself, called Franz Kafka's It's A Wonderful Life, starring Richard E Grant and Ken Stott. In 1995, it won an Oscar for best short film. Capaldi was exultant. Of course he was: he had, very suddenly, arrived.
"Being up there on stage, collecting my statue in front of all my idols, was... was amazing," he says. "The feeling, I have to tell you, was practically sexual. This, I thought, this I could get used to..."
In his own way, Capaldi then became the semi-toast of Hollywood. He got invited to parties, his talent sufficient enough to warrant the pressing of flesh with the good and the great of the film industry. Offers came - if not flooding in, then trickling. There was the opportunity to direct Loveboat: The Movie and Frosty The Snowman, both of which he said no to in favour of writing and selling a script to Miramax, and then getting his name attached to a remake of The Man With The X-Ray Eyes, until somebody surgically, and unceremoniously, unattached it six months later.
"Oh God," he says, "I made huge mistakes in Hollywood, so many that I effectively lost count. But then, you know, I wasn't really sure what I wanted to do."
He ultimately chose to concentrate on the Miramax screenplay, a genre piece called Moon Man, which he fine-tuned for over a year until the production company's boss, Bob Weinstein, summoned him to its New York office with good news: the project had suddenly been green-lighted. " But something happened while I was in the air," he recalls now, the memory still biting, "and by the time I landed it was off again."
However, at this stage he was still blissfully oblivious. Upon arrival, a car was dispatched to drive him to Miramax's Tribeca headquarters, Capaldi anticipating a long lunch and the popping of several champagne corks.
When he arrived, the actor-director pressed a generous tip into the palm of the driver and walked with pomp and ceremony, towards his glittering future. Fate then delivered its mallet blow. "Ten minutes later," he says, "I was back in the car, dream over." He pauses, the punchline so sourly poignant it still hurts to recount it. "The driver gave me back my tip." And that was the end of his Hollywood dream.
Capaldi refused to be entirely defeated. In 2001, he wrote and directed Strictly Sinatra, a mess of a film in which everything that could have gone wrong did (including, tragically, the death of one of its leading men, the venerable actor Ian Bannen), its ultimate box-office disaster status a foregone conclusion.
And so he returned to his day job, TV acting. While far from the excitement of Hollywood, it provided regular pay cheques, which his wife, daughter and bank manager were all grateful for.
"In many ways," says the 46-year-old, "I'd settled down to my twilight years, popping up on things like Judge John Deeds and Foyle's War, as well as the occasional horror movie shot in Romania [ Wild Country] that nobody will ever see. To suddenly get something as exciting as The Thick Of It, then, really is terrifically exciting."
But not, clearly, exciting enough, because he continues to plug away as a budding auteur. Next year, he plans to direct another of his screenplays, The Great Pretender, for the big screen. The film, about an alcoholic film star who absconds from the film set to be replaced by his lookalike, is slated to star Ewan McGregor.
"It could be a classic comedy," he says with admirable optimism. He smiles the smile of bitter experience, and attempts to sum up his doggedness in a media-friendly soundbite. He duly succeeds. "I suppose I just like being arty," he says. "That's all. Arty."
'The Thick Of It' begins on BBC4 on 20 OctoberReuse content