Can you stretch to Sketch?

The other day, Mourad Mazouz read a story about a French marathon runner who was attempting an 8,000km traverse of the Sahara desert. "Do you ever think about stopping, giving up and climbing into the support truck?", they asked the athlete. "No," said the runner flatly. "Of course, sometimes I think to myself, 'Why am I doing this? I must be completely mad.' But giving up is never an option."

The story hit a nerve with Mazouz, or "Momo" as he is better known (he also owns the Moroccan-themed Momo restaurant on Heddon Street) because launching Sketch, his new Conduit Street bar/restaurant, has been the catering industry equivalent of the world's most gruelling, Iron Man triathlons.

The project started four years ago when Momo discovered a grand but derelict 18th century former Christian Dior showroom. The listed building's roof was caving in and the structure was unsound. Friends told him he should forget about it and enjoy the success of Momo, which was still packed every night.

Undeterred, he persevered with his vision, employing the young French hotshot Noe Douchafour Lawrence as a design partner. Wild, fanciful plans were drawn up, a Hollywood budget of £5.2 million was decided upon and an extremely wealthy but patient and anonymous investor found.

Then the nightmares began - spiralling building costs, hidden structural problems, finicky British Heritage demands, unreliable contractors. Some say the eventual cost was more than £12 million.

Momo himself is now completely grey. And he's still not happy. He has been working 15-hour days for as long he can remember: "It's not easy. I am brave, ambitious and maybe a bit stupid," he says, insisting that he is not in it for the money. "I do this for the love of being a host, to provide hospitality."

He casts a weary eye around the small but impressive room (think; half Korova Milk Bar, half Austin Powers shag pad), points out the funky, kinetic art sculptures, the original Panton chairs, the 1970s redux tables and the Tom Dixon lights and sighs. "I will not make one pound out of this place for at least 10 years and upstairs at the Lecture Room restaurant I will never make one single pound."

Since Sketch's labyrinthine fun palace opened a few weeks ago, Mick Jagger, Donatella Versace, Kate Moss, Nancy Dell'Olio, Jay Kay and Robert Pires have visited and all raved about it. Jason Donovan took a pee in the Swarovski-sponsored jewel-box of a loo on the landing and exclaimed: "Jeez, I'm glad I'm not doing drugs any more."

Such praise has delighted the hardto-please Momo. But he is not happy with the way the press have focused on the steep price of dining upstairs where Pierre Gagnaire, the three-star Michelin Parisian chef, presides.

Momo reckons it is worth every penny. "What we're offering is an unforgettable experience, and you can eat downstairs for around £80. This is a gastro restaurant, the produce is the best in the world - we have 35 staff looking after 30 people.