Directed by Keith Fulton and Louis Pepe. Featuring Terry Gilliam, Johnny Depp and Jean Rochefort.

Never one to play it safe with studio films, Terry Gilliam is one of the great directors who often seems to bite off more than he can chew but always comes back for second helpings. He's had major hits ('The Fisher King', 'Twelve Monkeys') and flops ('The Adventures of Baron Munchausen', 'Fear and Loathing in Las Vegas'), yet his sense of fun and optimism remains constant. But when you have to trim the budget of your dream film on Don Quixote to just $32m, you can't get all your actors in the one place at the same time, your soundstage is anything but and your leading man has to go home to France because he's ill, just how easy is it to keep a smile on your face?

The fact that they'd trailed Gilliam for their 'Twelve Monkeys' spin off 'The Hamster Factor', meant that documentary makers Fulton and Pepe had a rapport with their subject long before they arrived on the set of 'The Man Who Killed Don Quixote'. But the beauty of this film is the level of access the director gives them - even when his cherished project unravels in the most heartbreaking way possible.

Sixty-two-year-old Gilliam had wanted to make his version of Quixote - involving Johnny Depp's ad exec from the modern day travelling back in time and becoming Sancho Panza - for over 10 years and described himself as "the best director on the planet to do it". So when European producers finally came up with the money, it seemed as if he was on his way. But right from the start they clouds were gathering…

A seriously curtailed budget meant there was no room for mishaps, meaning that Fulton and Pepe find a director and his team stuck in a very serious game of catch-up long before the cameras start rolling. Just when things can't get any worse they do: the first day of shooting is ruined by military jets on the soundtrack, followed by flash floods which almost wash the set away, then Gilliam's Quixote, Frenchman Jean Rochefort, suffers a double herniated disc and can't get on or off a horse. And when Rochefort has to travel back to France for treatment, it's discovered that his illness isn't covered by the insurance and the whole project will have to be scrapped.

What 'Lost in La Mancha' captures is filmmaking at its very worst. Unlike the 'Apocalypse Now' documentary 'Hearts of Darkness' there's no big victory or acclaim waiting for Gilliam at the end. There isn't even a movie, just a director looking at the few finished scenes he has and wondering what might have been. The twist is that you'll leave the cinema with more admiration for him than you had before you went in. Gilliam's level of enthusiasm and relentless desire to keep on going is infectious - you may even jokingly wonder if he could've supplemented the Quixote budget by writing a best-selling motivational book.

And while some would argue that Fulton and Pepe's film is so good because everything falls apart for Gilliam, the fact is that 'Lost in La Mancha' might actually help him get the money to make the film he deserves in the long run. Right now, he's trying to get the rights back from the insurance company. After seeing this you'll be very tempted to send him a cheque.

Harry Guerin