One of Britain’s national treasures – although some council officials might argue that point – Banksy the street artist, public-space jester and museum curator is famed for his snogging coppers, simpering apes and cheeky rats.  Now Banksy takes his very own brand of ‘Irony’ into the cinema directing ‘Exit Through the Gift Shop’.

It is a beautifully layered pseudo documentary about street art which turns into a documentary about Banksy and changes again into a documentary about the documentary before the paint can dry on his latest work.

At the centre of the film is the friendship, or is it, between Banksy and one of his apparent greatest fans, fashioning stalker like qualities, one Thierry Guetta.  A French-American who films every aspect of his life in a desire to want to be a film-maker.  Thierry is drawn into the street-art scene through his cousin, Space Invader, whose thing is to paste up icons from the classic video game.  There is great footage of the early nocturnal shenanigans of artists who have since gone on to be collected – such as Shepard Fairey, best known for his Obama “Hope” poster.

The missing piece from Guetta’s collection was Banksy.  So the two team up and we are treated to glimpses of the artist – or rather body parts of the artist – at work in his studio.  Most amusingly, we see him placing an inflatable Guantanamo Bay inmate in Disneyland’s Rocky Mountain Railroad ride, which leads to Guetta being held for four hours by the Disney police.

The first completed documentary, however, is no good.  Banksy tells Guetta to go and be a street artist while he sorts the footage out.

Guetta takes him at more than his word employing other artists to manifest his ideas, he creates hundreds of works of art, and publicises a massive exhibition in Los Angeles with a supporting quote from Banksy pasted on billboards.  The rest…..well for you to watch his space!

Sundance has shown films by unknown artists but never an anonymous one. Banksy turns the tables on the only man who has ever filmed him, creating a remarkable documentary that is part personal journey and part an exposé of the art world with its mind-altering mix of hot air and hype. In the end, Exit Through the Gift Shop is an amazing ride, a cautionary modern fairy tale . . . with bolt cutters.