Jamie’s Italian is squeezed into the Devonshire Arms on Denman Street, Soho, borne on the duplicitous winds of TV shows and book deals. It’s an odd fit, like a Flump meeting Dante. The Devonshire was a pub at the end of the world, a Victorian dystopia made of violence and despair. Now Jamie Oliver — an aghast teenager running to fat even as he declares war on the Turkey Twizzler and the civilisation that wrought it — has sucked it into his empire of Jamie’s Italians (there are 41, from Aberdeen to Gatwick), installed a roof terrace and written ‘Established 2014’ over the door.

At first glance, Jamie has done nothing to the Devonshire Arms. It is still a grim London pub, now struck down with a late-term identity crisis. He has not even removed the signs that told the very drunk they were in the Devonshire Arms, rather than New York, or a swimming pool, or hell. There are green leatherette banquettes, brown plastic walls masquerading as wood panelling and a hideous air-conditioning system hanging, like a dead TV alien, from the ceiling.

Explore further, however, and learn what new horrors planning restrictions can summon in a Victorian pub that has been bought by a fake-revolutionary chef expanding, in every sense, too fast. There are metal staircases and crazy art to invoke edge when there is none; Oliver, for all his anti-establishment posturing, is a conservative force. Women who feed their children chips through the barbed wire at school know him as their enemy. There are five cramped and sweaty floors of it; a 440-cover restaurant lurks behind the signage. It is a Tardis.

The service is a tribute to Oliver’s TV schtick — chaotic love-bombing. The waiter sprints through the specials, waving his arms, as if conducting antipasti. Presently he brings Jamie’s Ultimate Plank (what to say?) — a small tree held up by two empty tins of tomato puree. It carries a series of mediocre cheeses and meats and salads, selling itself by size, improbability and size again; it is obliviously pornographic and I do not want to eat it.

Floored by the plank, so to speak, we progress through the enormous menu; enormous, in menus, usually bespeaks anxiety and, in this case, confusion about geography and provenance. Oliver likes to place the word ‘Italian’ before dishes that are not Italian, as if wishing it will make them so: there is Crispy Italian-Spiced Duck Leg and, more preposterously, Italian Steak Frites. This is larceny: it reminds my companion of the time the owner of a Milanese trattoria insisted he had invented Sachertorte.

It is boastful too: Our Famous Prawn Linguine. The Ultimate Burger. World’s Best Olives on Ice. Award Winning Pecorino & Chilli Jam. Epic Brownie. This is narcissism. It is like eating a certain kind of journalist.

The pasta is well-seasoned but overcooked; the Crispy Italian-Spiced Duck Leg has never dreamt of Italy, let alone quacked there; the Italian Steak Frites are French Steak Frites.

All this is a hoax inflicted on the clients, who have been enticed away from Pizza Express, where they really wanted to eat, by Oliver’s fame. (Pizza Express is a very good restaurant.) It is a restaurant for Alan Partridges who dare the poisons of Soho and are fleeced for their trouble. It may be in Piccadilly Circus, but spiritually it is a Surrey pub for divorced dads on Sundays; an ‘Italian-Style’ Harvester selling overpriced food that does not know where it is from. (Harvester is not a good restaurant.)

Fennel ‘rubbed’ pork scratchings tell us all — this is a child’s restaurant.