Pure genius of the caring hitman

He has a major presentation to make to Citroen the following day, but Mark Wnek has more pressing matters on his mind. Campaign has just written some tittle-tattle alleging, among other things, that he wore the same clothes for three days at the Cannes film festival. "I mean everyone knows I'm one of the vainest people alive," he burbles. "What do you imagine people will think, John?" Without pausing for a reply, he picks up the phone to put the same question to someone else.

All of which has rather shaken my preconceptions. Mark Wnek, creative director of Euro RSCG Wnek Gosper, the current darling of the advertising world which tops the new business league and has recently picked up three of the most glamorous brands of the 90s - Hooper's Hooch, Wonderbra and Haagen-Dazs, has a reputation for being surly and difficult. Not to mention menacing. When he first got his name above the door in 1994 staff presented him with a cardboard axe after his first round of firings and since then he has done little to shake off his Darth Vader imagine. So it is something of a shock to come face to face with a rather emotional neurotic.

But he is nothing if not a good salesman,and I suspect that part of his neurosis is pure charm offensive. He's a large man with closely cropped hair and with his bright yellow shirt, blue oval specs and slightly edgy Jack Dee delivery, he looks and sounds more like a minder than one of the top creative directors in the business.

"Advertising isn't about creating works of art to return to and discuss; it's about making an immediate emotional impact," he says, clicking his fingers to emphasise the point. "You hope that people will see your ads more than once, but you can't count on it as they may be taking a leak or making a cup of tea. There's no point overloading people with facts and figures, because everyone is bombarded with so much information these days that they have an inbuilt 24-hour anti-bullshit radar. If they think you're trying to hard sell them, they just switch off."

All this from the man who,at other points during the course of the interview, quotes Voltaire in an accent any haut bourgeois Parisian would be proud of, and admits that he got his first job with Ogilvy and Mather by ripping off a description of Renoir's painting technique at his copy test.

Getting to grips with Wnek is no easy matter then. "I spend my whole life having endless short conversations," he says. "I can give you my life and soul for three minutes, but after that I start looking out the window." A short attention span and a workaholic lifestyle - he regularly works from 7am till midnight - has played havoc with his private life and he has been divorced twice but has made him a natural for a medium that thrives on getting the message across in 30 seconds or less.

The irony is that Wnek has made his name by making ads that have lasted a great deal longer in people's memories. His "pure genius" works for Guinness at O&M, "smooth-talking bar steward" for Heineken and Nigel Hawthorne and Tom Conti Vauxhall Astra campaign at Lowe Howard Spink were primary reasons for Euro RSCG head-hunting him as creative director. The good work has continued. His Peugeot 406 ad - you know, the one with the little girl in the red coat, was recently voted the most popular car add of all time.

Euro RSCG was a largish agency going nowhere fast when Wnek, and nuts and bolts man Chris Pinnington, were brought in by its French owners to revamp the image. "I was horrified by the complacency when I first arrived," Wnek says. "If I got a reputation for being a bit of a bastard in this period, it was purely because I was scared stiff. We had over pounds 100m of billings when we took over, but the business was so badly run I expected the clients to leave in droves. And when you're not sure whether you'll still be in business a month down the line, you don't have time for a touchy-feely approach."

But the clients stayed and when Brett Gosper joined as chief executive from Euro's French office the following year, the agency finally found its true identity. Its new business record is phenomenal with more than pounds 150m of new billings within the last year: apart from Hooch, Wonderbra and Haagen-Dazs, Euro has also picked up Airbus, Evian, Cadbury's Fuse and Intel, to name but four.

Even the agency's riskiest strategies seem to be paying off. Last year it publicly fired Guinness on the front page of Campaign, havingly informed the brewery just before publication. And yet Euro got away with it. Within months it had signed up with Bass.

I suggest that sex is the main reason for Euro's success - it has perfected the art of using sex to sell. The Peugeot 306 campaign ran on the premise that a normal relationship continues even after the arrival of children; the 106 ad, which The Observer refused to run, featured a girl wearing a pair of white knickers and car tattooed on her stomach. Small wonder then that Wonderbra and Haagen-Dazs have rushed to join the in-crowd.

Which brings us nicely on to alcopops. Euro has put itself in the firing line by taking on the Hooper's Hooch account and has been forced to fend off criticisms that it is guilty of promoting alcohol to under-age drinkers. Predictably, Wnek mounts a robust defence.

"We've used an actor in his mid to late 40s, and we've highlighted that it's a drink to be treated with respect," he says. Oh really? One can't help feeling that the wackiness of a man in a yellow frock - soft on the outside, hard on the inside, geddit? - is just the sort of image to appeal to young consumers.

But it has got away with it and the success has brought it into new areas where it has still to prove itself. Being brought in by Airbus to take on the global might of Boeing is a massive challenge, where Euro's traditional British strengths of sex and wit have little role to play. Likewise, dealing with major corporate clients, such as Procter and Gamble, which has always adopted a conservative attitude towards advertising, is likely to be an uphill struggle.

Wnek seems unfazed. "There are times when you get fed up with acting solely at a local level and you want to see how you cope on a larger stage," he says. And if Wnek does manage it, what then? Like many dream merchants, he longs to be a director of Chelsea FC, and his only major regret is his failure to win the BT account, though he remains bullish that it will eventually be his.

Yet one senses a restlessness about him. He seems to have no real interest in money; he drives a second-hand Range Rover, lives in a comfortable house in Fulham and his only noticeable indulgence is to treat The Ivy like a staff canteen. "I love my job, but it sometimes isn't enough for me," he muses. "Often it's only the thought of 174 people and their families depending on me that gets me going." Can this man be all heart?