Talk to any British first-time film-maker and you will hear a familiar story: a catalogue of tantalising near-misses, a saga of funding raised then snatched away at the last minute. There is a familiar refrain: “We’d like to give you the money but you’ve never directed a feature film before so we can’t.” It’s a wonder anyone ever manages to make a movie.

The writer-director Paul Andrew Williams spent the best part of two years being buffeted to and fro by the whims of the film industry until he finally snapped. “I had another film in development, a £2.5 million feature. It had money, then it didn’t have money; it had actors and then it didn’t have actors. It was just going through hell.

“I found that it had been put back again on a Friday, when I was on my way home to Devon. As soon as I got home I started writing a script. I sat in the front room, the special front room — Christmas and holidays, the one with a nice telly in it. And on the Monday it was done. Literally three days.”

The script, hammered out from an idea he had had a few weeks before, was a lean, urgent thriller set over 24 hours in London’s murky underworld and in a wind-lashed, out-of-season Brighton. It evoked British classics from a past era — Mona Lisa particularly, and to a certain extent Get Carter — but had a voice distinctly its own. Its title was London to Brighton.

Given the subject matter of the screenplay — underage prostitution, cowardly, bullying pimps, murder, revenge — it’s perhaps inappropriate to use the term “fairytale success story”. But even Williams appears as though he can’t quite believe his film’s journey from script bashed out over the course of a weekend to one of the most celebrated British films of the year.

Apart from one rewrite to change the story into a non-linear structure, what ended up on the screen was pretty much what Williams first wrote. “I didn’t change any of the lines, just the order of the scenes,” he says.

A few days after he had written his first draft, he had a meeting with the man who is credited as the film’s executive producer. Tony Bolton had helped to fund some of Williams’s short films and responded positively to his suggestion: “If you can get me 60 grand, I’ll give you half the company. He said: ‘That sounds good, show me some sort of business plan’.”

The £60,000 was a bit of an arbitrary figure as Williams had not actually calculated a budget. “If we got that amount of money we’d do it for that amount of money. If we got 30 grand, we’d do it for 30. If we got whatever, we’d do it for whatever. It ended up costing £80,000 to actually get to a point when we had finished a cut and put the music on. After writing it we were in pre-production within four months.”

The realities of ultra-lowbudget film-making are draining. To make the film for the money available, Williams had to make compromises. He managed to shoot the picture on film rather than digital videotape, but had to defer his own fee for directing. He was signing on for unemployment benefit throughout the production.

“I’ve been on the dole for ages and it’s pathetic,” he says. “But my whole thing was, you either be a director or you be a barman who tries to direct. So I stuck it out.”

His overriding memory of the shoot is of the exhaustion. “There were times when we were driving two hours to the set, filming for 18 hours and driving two hours back. It was the most scared I have ever been. We had all the windows open and the music on full blast because we were frightened of falling asleep.”

A former actor himself (he gives himself a blink-and- you’ll-miss-it cameo early in the film), Williams is quick to give credit to his impressive acting talent. He had worked with Lorraine Stanley and Johnny Harris before, in a short in which both played the same characters they play in the film — Kelly the streetwalker and her bullying pimp, Derek. “I’d always wanted to work with those two actors again,” Williams says. “We’d always kept in touch.”

Both are outstanding in the film. Harris manages to give the reprehensible, manipulative Derek a vulnerability and a humanity that catches you off-guard, while Stanley’s Kelly is sick with guilt at her part in procuring an 11-year-old girl for a paedophile client — it’s a raw and gutsy performance. The film should launch the careers of everyone involved.

London to Brighton premiered at the Edinburgh Film Festival this year to resoundingly positive reviews. “There we started to realise that people liked the film,” says Williams.

What’s changed since Edinburgh? Williams has finally come off the dole and has another film in preproduction. He found himself besieged by American agents and managers after the film screened at the Toronto Film Festival. He still, he says, sometimes cries when he watches it. “To be honest, I know I’m where I am through hard work and tenacity, and never giving up. But (the success) freaked me out a lot. I still am a bit humbled by it. I find it a bit uncomfortable.”

London to Brighton is released on Dec 1

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