The first glimpse we get of him conveys exactly the right impression. He's bombing down a contorted country lane about the width of a blood vessel, his hand jammed down on the horn. "That's a short cut, that is," he says as he emerges just about unscathed. "Saves 30 seconds. Takes 10 years off your life."
A cross between Alf Garnett and Barbara Windsor's gentleman friend in EastEnders, middle-aged Essex man redrawn by Hogarth, Barry is naturally unrepentant about taking the punters' dosh.
"Change money, take prices, and win," he says cheerfully. "That's how easy this game is."
A brush with the coronary artery police warned him off the lifestyle that was killing him. He used to "get up at nine, go to the races, finish at five, into Romford dogs until 10.30, home 10.45. The wife knew there had to be a bottle of scotch, a bottle of lemonade, a big jug of ice, a pound of steak, two fried eggs, pounds and pounds of chips, six slices of bread and butter. I'd knock out the bottle of scotch by half past midnight and go to bed."
Surprise, surprise, "after 15 years of that, in the middle of the night I woke up and felt queasy." Well, yes. Following his doctor's advice saved his life, he reckons, though you suspect the main pillar of his health plan involved his wife consuming more greens. A few minutes later, they're eating together: she nibbles at a rocket salad while he's polishing off a big lump of steak, two fried eggs and pounds and pounds of chips.
He talks about the golden age in the 1950s and 60s, when tipsters did not have the information they do today. "Punters were throwing it away," he says. "I joined in the 70s, the good old days - the XJ10 Jag, mixing with the toffs, St Trop in the summer, skiing twice in the winter. They were the 70s. Now we're in the hard-up 90s."
But not that hard up, despite the film's best efforts to be balanced about protestations of poverty. In the kitchen at home, he explains why he's only minor league: the bread bin's the grandstand, a sliced loaf is Tattersall's, a tomato's the winning post and the cherries are the bookies. Unless you're right at the front you're shafted. He's been waiting 29 years to get one of the prime sites.
There is hope, though, as hereditary pitches are to be abolished, and Barry is desperate for a sniff of the serious money. As one of his colleagues puts it: "What I need is not only all the bookmakers to die but the sons as well. My all-time prayer is something like a terrorist attack at Ascot, or the stand falling in."
"I didn't say that," says Barry, happy for once to be upstaged. "I just hope they all pass away quietly."
Though we see him take seven grand from one race, his wife is unimpressed when he comes home with the wedge. "That's not ours," she says. "It's there to be lost." And a few shots later, as he loses pounds 6,500 - "sorry about that," says one punter as he walks off with three thousand - Barry turns to the camera, happy to be vindicated: "You satisfied?"
He is not above tawdry little stunts like getting his niece and her mate to hang around his pitch dressed in bodypaint - though you wonder how much of it was about putting on a decent show for the telly people. At Royal Ascot he fetches up in a ridiculous all white number, like something left on the cutting room floor by Peter Greenaway. Still, poncey though he looks and entertaining though he is, even he can't surpass the antics of the trashed toffs around him.
"My accountant won't go anymore," he says. "His wife said, `This is the last time I'm going to Royal Ascot. The last time, we went into the car park and there was a couple fornicating'... That's what happens at Royal Ascot: you go out posh and you come back cockney." Indeed, the sight of Middle England making a paralytic ass of itself is worth a docusoap of its own.
Even better for Barry, in a postscript we learn that being given pounds 250,000 by a "friend", whatever that means, has enabled him to acquire 12 front- line pitches. "We're out of the mire," he says, "we're up and running. There's food on the table tonight. What colour are my trousers?" he asks, turning his backside to the camera. "All right?"
I don't know what odds Barry was giving about Kevin Keegan becoming the new England football coach. After seeing Ghana win last year's Inner City World Cup (Fusion, C4, Sunday), it's clear what the FA has to do next to fill the Job From Hell.
The Ghanaians, you see, had six managers. That's not one manager-in-chief and five glorified kit men; it's six gaffers, enjoying equal status and an inability to agree on anything, the team's progress punctuated by bursts of managerial aggro.
"When it gets too much the players get confused," one of them yells, and though it was hard to disagree, it did not stop them beating Bangladesh to take the title. As the winners danced round the pitch, one of the Gang of Six revealed the real secret of their success: "We never say die until the balls are rotting," he says. "And have you ever seen balls rotting?"