Is she the real thing or is it all just a racket? People have been wondering this ever since Charles Saatchi swooped on the art work of some ex-stripper and put it up in his 2004 New Blood show. Stella Vine’s garishly disturbing portraits were bound to stir up a media storm. She had painted Diana, Princess of Wales, with blue eyes boggling and lips dribbling blood, calling for help from her dodgy butler. “Hi Paul can you come over I’m really frightened,” Vine scrawled across the canvas, like some teenager lip-sticking a message on her mirror. She had painted a picture of the heroin addict Rachel Whitear, whose death with a syringe in her hand had made newspaper headlines. The girl’s parents were contacted so that they could protest their outrage.

Overnight, Vine found herself flung from obscurity into the public spotlight. And now, three years later, she is being given her first exhibition in a leading British gallery. A huge show of her work, its hundred or so images including her controversial Diana paintings, a host of celebrity portraits as well as the faces of characters in her own family story, is opening at Modern Art Oxford this week. But does she really merit it as an artist? Can her paintings stand up to scrutiny? Or is her work just another example of that easy sensationalism that stages a raid on the popular imagination? In one sense it’s easy to see the fascination of Vine. Taking up our positions of voyeuristic privilege, we can revel in the vaguely salacious life story of a young woman which has been peddled to a prurient media and which, for your delectation, I am about to repeat.

Stella Vine’s real name is Melissa Robson. She was born in 1969 in the picturesque Northumbrian town of Alnwick, where she lived with her emotionally elusive mother, a seamstress called Ellenor, and an affectionate and much-loved Auntie Joan. But when she was 7 she moved to Norwich. Her mother had fallen in love with a man whom, Vine intimates, subjected her to mental and perhaps sexual abuse. At 13 she ran away, first going to London then returning to Norwich where, living in a clapped-out bedsit and signing on under a false name, she got pregnant at the age of 16 by the caretaker of her derelict block.

Returning to London with the baby, she lived the desolate tower-block life of a single mother on benefits, struggling her way through drama school and then dragging her son round regional theatres as she took on a succession of ever less remunerative roles. She ended up as a waitress, then a hostess girl, then a stripper as she struggled to foot the bills and better herself so that she could pursue her creative ambitions. In 2000 she started classes at an art school in Hampstead. “Forget about drawing, get the paint and colours down,” the teacher said. And she did, splashing down pictures in gaudy acrylic. She fell in with the Stuckists, a clamorous cult of resentful artistic also-rans who, convinced that their talents have been by-passed by a Tate-led fad for conceptualism, protest publicly each year at the Turner Prize award dinner. And she had a very brief but vitriolic marriage in 2001 to their slightly sinister leader, Charles Thomson.

Picked up at various times in her life by cocaine, Prozac and the occasional sugar daddy, she found success through intensive therapy and the marketing mogul Charles Saatchi, who, desperate to pad out a show of upcoming painters, stumbled across her Diana pictures. She had transferred all the emotions from her mother’s death on to the princess, she suggests, and she let them slop straight on to the canvas.

These are the sort of canvases that she sells for as much as £20,000 – and perhaps more now that she has received an official stamp of approval from Modern Art Oxford. Are they worth it?

The images on the gallery walls make an immediate impact. Celebrities from the Beatles to the Brontë sisters to Big Brother’s Chantelle goggle down at the viewer with vast Barbie-doll eyes. The spectator is fixated by a sense of sudden recognition and by the colours, which are as lurid as a tube of fizzy sweets. He is amused by the flashes of inappropriate humour and, occasionally, by the accuracy of the observation. Here is Courtney Love, crouched like a rabbit in the dazzle of the camera flash-bulbs; the London gallery owner Sadie Coles manically flicking her hair; Pete Doherty singing in his typical slope-hipped pose.

But there is something more complex going on. These images speak about more than the simple desires of a starstruck teenager. They are the painted projections of Vine’s own self. They arise from the slightly spooky ambition of a former method actress who has tried to put herself into her character’s persona, to actually become the person she painted. And Vine can’t be unaware that she in a sense has succeeded. Through the controversy she has created, she has attained the sort of fame that belongs to her subjects.

Vine’s paintings look like “something that might hang on the park railings”, one critic railed. But if Vine was a park railing painter she would try to make the pictures neater, more perfect. Instead they are deliberately left raw. They have a naive power. When she wants a dancer’s dress to look swirly she just swirls the paint across it. She applies make-up colours to the surface of her faces as subtly as a clown’s mask. Vine wants to appeal to some direct response. It’s all there on the surface.

And yet this is the surface that is cracking. Look at her Kate Moss, for instance. The spaces between her cutely imperfect teeth are crammed with darkness. Her smile is as taut as a sneer. The babydoll palette of Vine’s pictures turns acid. The colours are souring. The mascara runs with tears. The dreams are curdling into the ghastly self-confessional parodies of the reality. The highly polished Vogue aesthetic is turning into the trashy Heat snap. We can’t dismiss these paintings as a mere racket – not in a world in which the racket has become the real thing.

— Stella Vine: Paintings is at Modern Art Oxford (01865 722733) until Sept 23

Stella Vine: life as art

1969: Born Melissa Robson in Alnwick, Northumberland

1982: Leaves home, aged 13, because of her stepfather

1986: Gives birth to a son, Jamie, at 17. Moves to London to attend drama school. Works in a hostess bar and as a stripper to support herself and her son

1995: Changes name to Stella Vine

2001: Embarks on a day-long marriage to Charles Thomson, co-founder of the Stuckist movement. He has since exhibited semi-pornographic portraits of her

2004: Charles Saatchi buys portraits of Diana, Princess of Wales, and the heroin addict Rachel Whitear

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