The members of the camera crew following him around Soho are, to the last man and girl, totally smitten. Yet, here we are on Bateman Street, outside West One Television and opposite the Crown and Two Chairman, being harangued by some trendy middle-aged bloke. He's kicking up a right royal stink. "You can't film here. Who are you filming for, who, who?" The director quietly but firmly tells him "We are making a programme about Soho for LWT, we have permission to film here."
He obviously works in TV, our new found pavement-side buddy, because he rolls his eyes and groans, as if this explains it all. As we move on, the aggressive TV man yells, "You've sold your soul."
Alex James mooches on, shoulders hunched inside his charcoal-grey suit. The programme's makers could not believe their luck when he agreed to present 24 Hours in Soho. "Usually, I'm quite shy, but I wanted to do this. I've lived here for 11 years, this is home."
It is true that James has built up something of a traditional association with Soho; in fact, he and Keith Allen are picking up where your Jeffrey Bernards and your Keith Waterhouses left off. "Keith: naughty, dangerous, out of control, he's Soho," says James fondly. "I love the fact that there are 100, no, make that 1,000 geniuses getting drunk at any one time here."
At one period, James's and Allen's drunken capers, frequently accompanied by Damien Hirst before his move to Devon, regularly made it into the papers and passed into Soho legend. (There was the time, for instance, when Allen and James bought a tramp outside the Groucho and made him their slave for a week.)
While he clearly finds the whole thing rather embarrassing ("It's like 1995 all over again," he mumbles) his passion for the area is plain. "When people say the word, 'London', you don't imagine Chelsea or Notting Hill. Soho is its defining area. When I first moved to London to go to Goldsmiths College in New Cross, I didn't realise you could actually live in Soho. When I did, I was straight in."
Breaking into telly is clearly not his aim. "I won't be giving up my day job - I'm certainly not doing it for the money," he says of his £3,000 fee. "I feel I have a degree in Soho. I just love the way life spills on to the street here. It sort of bulges."
In the course of shooting, the team has gone to pay homage at Soho's most venerable institutions: Madam Jo Jo's ("the first club I ever went to in London"); the Colony Room ("like a greasy spoon caf? that serves booze, and I love the fact that the art on the walls in there is worth more than the Groucho's"); and Gerry's ("it's the best, and yet it's just a hole under the ground"). And the tour wouldn't be complete without The Coach and Horses, the French House and a strip bar called Sunset Strip.
Tonight, however, we start at the King of Corsica, a nondescript regulars' pub on Berwick Street. Friday night is karaoke night and a beery, football-shirted crowd are in full voice. While we sit in a corner waiting for James to do his link at the bar, some bloke called Chris does a weedy rendition of Great Balls of Fire. Next is Old Compton Street - "the beach we call it, we come here to watch people and look at the girls" - where James is accosted by two screaming queens dressed, barely, as a cowboy and an Indian, their perky, pointy packages jiggling away in their second-skin Speedos.
"This is the main axis," pronounces James when we reach Dean Street. "You've got the holy trinity of the Groucho, the Colony and Gerry's. We were in Gerry's the other night and this old thesp was there, telling his anecdotes. It was Bernard Montague from Butterflies, Wendy Craig's love interest, remember? What a name. He was so good-natured, sitting there, getting slowly drunk on wine. If London's a pub, then Soho is its bar."
James is happy to admit that Soho defines more than Blur ever has. "When I was young, I liked the idea of drinking for a living, romantic, elegantly wasted, ridiculous, in this whirlpool which sucks you in. That's what I aspired to being, one of those Soho idiot geniuses. I don't any more." For the past three years he has given up drinking for the first four, five and then, this year, six months of the year. "I was just sort of disgusted with myself. It gets a bit repetitive, drinking."
Rumours that Alex James is the new Jeffrey Bernard are untrue. The drinker's face is gone. In The Player, a once-hot style bar, James stands amid pools of spilled red wine and hordes of girls. Gamely, he agrees to hold a drink for the camera, and does a beautiful impression of that drunk's wobble, eyes half closed, swaying, grinning benignly, even though he is stone-cold sober.
We move on through the night and the street fills with an ever-drunker crowd weaving between the cars. James is shot climbing into a rickshaw ("Mile for mile more expensive than Concorde these things, great for getting home in, though"). It has begun to feel as if we are the only sober people. "Yeah, it's getting a bit less gentle now. But it's got to be a bit f****d, hasn't it?"
Before we part for the night he offers a final bon mot. "East London? It's got an edge, I suppose. But this place, it's got hundreds of years of history. And there are the seven sins right on your doorstep."