DAVID ELDRIDGE is a Monsterist — one of a group of writers lobbying for the opportunity to create big dramas for big stages. Now he has put his money where his mouth is.

Market Boy, directed by Rufus Norris, is the first new work by a young writer to be presented on the National’s main stage since Nicholas Hytner took over as artistic director in 2003. Can Norris and Eldridge cut it? Damn right they can. Like much of Eldridge’s writing, Market Boy is rooted in his Essex upbringing; unlike his usual social realism, it explodes with vivid theatricality. And it’s the most fun I’ve had at the theatre in ages.

It’s 1985, and shy, naive 13-year-old Boy (Danny Worters) is propelled by his single mum into seeking a job at Romford market. Norris presents the moment when Boy enters this scarily enticing world in the first of many coups de théâtre. Trembling on a stage bare but for a central, towering steel scaffold, Boy steps into a spotlight. Frankie Goes to Hollywood’s Relax pumps out, and, through a rear wall bearing a Tory electoral poster bursts a transit van.

It disgorges the skinny, pale figures of the shoe-stall traders and their boss, a black man with skintight ski-pants and an irresistible way with women.

They construct the market on a giant revolve before the astonished eyes of both Boy and audience. The stall is a place where every Romford Cinderella can feel like a princess; here Boy loses his innocence and learns lessons about love, sex and commerce. The market’s family atmosphere belies the ruthless individualism of Thatcherite doctrine, yet its unsustainable freneticism — captured in athletic movement by Scott Graham and Steven Hoggett of Frantic Assembly — suggests two kinds of party that cannot last, and will result in horrific hangovers.

The period detail are nostalgic but the scene is stalked by a nightmarish figure — Mrs T herself. She appears in various grotesque guises, swooping down from the flies on bat-like red, white and blue wings, or sitting next to a market trader-turned-City boy in his new Jag, dressed in blue underwear, a rosette on each nipple.

It’s bold, brash, and fabulous. It’s also overlong, and there’s little complexity to its parade of characters, including a trans- sexual fish-stall holder and a psychotic Falklands vet, now a record dealer, who discovers rave culture on holiday in Ibiza.

But nuance would be out of place in a portrayal of an era devoid of subtlety — and such audacity means you’ll forgive Eldridge and Norris almost anything. This production has a true spirit of daring — it’s exhilarating. And boy, it’s big.

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