Rob Brydon arrives at the Soho tearoom wearing a sensible pullover and seats himself behind a Diet Coke. He has come hotfoot from recording a television voiceover. When I ask what product he was advertising, he says warily: "It'll look hideous in print." But he tells me anyway: "Pot Noodle."
There you have the essence of Brydon, best known as the star of BBC2's cult hit Marion and Geoff. Not the Pot Noodle part. That would be absurd: imagine the kind of person whose essence could be likened to a Pot Noodle. No - it is Brydon's fear that his words will betray him that characterises his responses. He might be concerned that his talents cannot adequately be captured in ink. He is, after all, a dazzling impressionist. But it won't benefit you to know that he can do a mean Ronnie Corbett when you cannot savour it with your own ears.
Throughout the interview, Brydon augments his replies with suggestions and worries. He prefaces an anecdote by fretting that I will render it unfunny. "Whether it'll come across, I don't know. These things always sound better on the spur of the moment. But, well, OK. I'll trust you to decide." After which the anecdote is scarcely worth the telling.
"You should write, 'He smiled' after that," he advises, following a delirious skit in which he has imagined a wild weekend spent "whoring" with Corbett. "Don't put 'shagging'," he says, after using precisely that word. "Put something like 'having sex'." Alterations are to be expected at the editorial stage, but this is my first experience of having a feature edited before so much as a comma has hit the page.
It's ironic that Brydon should display such a fixation with language when the character he's best known for is unable to comprehend the words that are flooding out of his own mouth. Keith Barrett is the crumpled Cardiff divorcee in Marion and Geoff, the series of grimly comic monologues written by Brydon and Hugo Blick. Keith's inability to read a situation verges on the autistic. A typical Marion and Geoff moment will show him addressing his in-car camcorder in his minicab, crowing cheerfully about some petty triumph or other, only to lapse suddenly into a despondent silence as he realises that he's been sold a pup: for example, that the bank manager's idea for clearing Keith's £40 overdraft by foisting upon him a £3,000 loan was not so altruistic after all.
"I can't always see what people mean about the bleakness," says Brydon, "but in the last series I did think, 'Oh dear, we're putting him through the mangle a bit.'" He sucks the air through his teeth. "It's not an easy watch."
The hippy mechanic in Alex Cox's cult movie Repo Man observed that "the more you drive, the less intelligent you are," and in Keith's case you couldn't argue that a life behind the wheel has not contributed to his mental erosion. He addresses the audience exclusively from the driving seat, though that is the last position he could be said to occupy in his own life. Despite this, he can see the positive side in everything: his wife Marion's affair, his estrangement from his "little smashers" - his sons Alun and Rhys - even the doubts cast over his younger son's paternity in the second series, which saw the show's 10-minute slivers upgraded to unbearably dark half-hours. It is likely that if Keith ever set eyes on a mushroom cloud, he would chirrup: "Well, yes, it's the end of the world. But it's something to tell your grandchildren, isn't it?"
"I was glad to get to the end of the last series," sighs Brydon, "because I had taken on Keith's persona. My friends noticed that I had that look about me." By way of explanation, his eyebrows levitate into his hairline while his mouth spreads into a baggy smile. He gazes around the cramped tearoom with the kind of awe that most people reserve for the Grand Canyon. "Mega!" he coos in perfect Keith-ese. "It's like another world, isn't it?"
It's disarming how that subtle facial adjustment transforms him instantly into Keith. "Well, I look like him," he deadpans. "Uncanny, isn't it? Of course, a lot of the emotional scenes are done with a double. I'm mostly used for the inserts. When you see a hand on the dashboard, that's me."
In truth, I had intended to compliment his acting: he is nowhere near as close to Keith as I'd imagined he would be. He seems placated. "I used to be very wary of doing Keith in front of journalists, because they usually take that line of, 'Oh, it's just him, he's the character,' and I always found that a bit demeaning. The implication is one of artlessness. But Keith is actually a combination of observation and what's already there. You become quite mercenary if you spot a failing in yourself. Whereas most people would suppress or correct their flaws, I find myself thinking, 'How can I use that?' If something happens that leaves me looking like a chump, half of me goes 'Grrrr', but the other half is going, 'Now, if that happened to Keith, I could take it a bit further.'"
It sounds almost therapeutic - a means of transforming personal discomfort into art. He pounces on the idea. "Well, yes, there you go! I think you could do a whole article on the stuff people come up with when they're writing, and to what extent it's..." His voice trails off. I think he was going to say "confessional". Certainly people have been quick in the past to draw comparisons between character and creator. Both men no longer live with their children, though Keith's forlorn attempts to negotiate access are not reflected in Brydon's harmonious relationship with his ex-wife. And both deserted Wales for London. "Someone once asked me, 'How did you get out?'" Brydon says. "It wasn't East Berlin, you know. It's only up the M4. You can be there in two hours."
He grew up in Baglan, near Port Talbot, and discovered an aptitude for comedy voices at an early age. "I always felt confident about my voice and my hair. My hair has since begun to let me down. And I had terrible acne. Professional acne." We compare scars. "Mine are worse than yours," he says authoritatively. "You look for people who have succeeded with the same drawbacks that you perceive yourself to have. There's James Woods, Richard Burton, Bill Murray. They're all scarred." He isn't eager to discuss the subject further while the tape is running. "But you and I could chat about it afterwards," he offers, with a flash of Keith's extravagantly misplaced generosity.
I catch the same expression later, when I ask about his children, who are aged eight, six and three. "I generally don't talk about them," he apologises. "But on the other hand, I love talking about them." He gives a sincere "I would if I could" smile. I think a person would get the same heartfelt response if they requested his PIN code, or his girlfriend's phone number.
It could be this air of openness that landed Brydon his first jobs in broadcasting. Before he had graduated from the Welsh College of Music and Drama, he was already an early-morning DJ, with stints on cable television to come. "The common take on me is Alan Partridge-style radio, Shopping Channel presenter, voiceovers. Yes, I did all that, and I've encouraged journalists to dwell on that side of things because it gives them an angle, and it gives me an excuse to do all my stupid voices."
He sounds tired of playing the performing monkey. Possibly to keep himself amused, he has developed a knack for deflecting unwelcome enquiries. When he says he hopes his children will be proud of his work in later years, I ask if his own father made him proud. "Well, my dad's a car salesman," he shrugs, "so I don't take pride in any specific sale he made. I can't say that the 1973 Triumph Dolomite he sold gladdened my heart."
After arriving in London, Brydon served time in the twilight zone of sitcomland (including Russ Abbot's Married For Life), landed offbeat bit parts (a peasant in First Knight, a traffic warden in Lock, Stock and Two Smoking Barrels, a floating head in Dennis Potter's Cold Lazarus) and amassed a small fortune from supplying advertising voiceovers - Toilet Duck, Bounty, Somerfield. "I do those Tango ones - you know, the guy in the helmet? Those are mine. You can forget you've done some of them. They come on and you think, 'This sounds vaguely familiar.'"
He's doing fewer ads since his own shows took off: the two series of Marion and Geoff, shepherded by his friend and mentor Steve Coogan, and Human Remains, in which Brydon and Julia Davis portray a rogues' gallery of dysfunctional couples, have been hits. Last year, he took Keith on the road in the Marion and Geoff stage show, which has now begun its two-week run at the Edinburgh Festival Fringe.
This spoof lecture, complete with slides, on the theme of making divorce work has given audiences their first chance to see Keith away from his car. The reaction to date has been mostly ecstatic, though there have been exceptions, sometimes from within the Brydon clan. "One of my relatives came backstage afterwards and said, 'Be honest with you, Rob. I dozed off for a while. I'm on nights at the moment.'"
A third series of Marion and Geoff will be a long time coming, if it comes at all, but Keith may yet have a future on stage. "I think if I wanted to I could bring him out every couple of years, looking at different subjects. This one's divorce, but it could just as easily be Keith Barrett's Night of Poetry." He makes Keith sound like a favourite coat. "I do feel like that. I'm very fond of him."
There has, inevitably, been talk of Marion and Geoff being adapted for the US. Brydon fantasises about Jeffrey Tambor - Hank from The Larry Sanders Show, easily Keith's equal in self-delusion - taking the role. That aside, he's not much stirred by the idea. "Everyone gets that call from America," he says. "Right now there's probably a call coming in for late night bingo on the Granada Men & Motors channel."
He isn't even certain that a US audience would get to grips with Marion and Geoff. "I heard about an American who watched an episode and said afterwards, 'God, you really wanna slap that guy!' I don't know if Americans could identify that much with a loser." He stops, cognisant for the umpteenth time of how his words will look on the page. "I mean, someone they perceived to be a loser."
'Marion and Geoff' is at the Assembly Rooms Music Hall, Edinburgh (0131-226 2428) to 17 AugustReuse content