Marc Evans's first feature, `House of America', sharply evokes the world of siblings trying to escape the confines of small-town Wales

"There's only one good use for a small town," Lou Reed once sang. "You hate it and you know you'll have to leave." That song, "Smalltown", will have chimed in the heart of anyone who ever tried to escape that place where men hunch in the corners of pubs marinating in lunchtime lager, and anything that stops still for 30 seconds gets swallowed by weeds or rust.

It's called Home. Teenagers slouch around its streets, complaining about it. Some of them get wise and leave. If not, they become their parents, and find the allure of the Radio Times and a comfy armchair difficult to resist. The young Welsh director Marc Evans was lucky. He got out. He studied Art at Cambridge, film at Bristol, made witty shorts like the bi-lingual Johnny Be Good and accumulated portfolios full of glowing reviews for his television work.

Now his first feature is poised for release: a strange, startling film about Sid (Steven Mackintosh) and Gwenny (Lisa Palfroy), a brother and sister trying to dodge a destiny which has more or less decreed that they are headed straight for that armchair, plumped cushions and all.

The film is House of America and the hell-hole in question is Banwen, a town languishing in Wales's industrial south. However, it becomes clear from the film's opening minutes that this is no dip in the grubby kitchen- sink of 1950s and 1960s social realism. The siblings, obsessed with On the Road, pine for their long-lost father, who has apparently upped stumps to follow his American dream. Sharing the house with them is their more pragmatic brother Boyo, while their deranged mother, who flips through empty photo albums reminiscing about the pictures that once filled its yellowed pages, might have wandered out of a Beckett play. Indeed, the friction between dreams and decay, stagnancy and soul-searching, creates a kind of Waiting for Kerouac.

It's undoubtedly a harsh landscape. But for something which ostensibly focuses on how small town life can damage your health, House of America is a surprisingly feral piece of work, steeped in mythology, surrealism and tragic humour. Fans of Dylan Thomas may be shocked to find a Wales so infused with Western iconography that you expect a gunslinging tournament to break out at any moment.

"It wasn't the easiest thing to persuade people to finance," Evans tells me. "Possibly because it sounds like some miserable documentary, whereas the film we wanted to make - and made - was very heightened and theatrical. The BBC had hold of the play at one stage and wanted to do the typical social realist TV drama. We had different ideas. When you do your first feature, you spend far too much time protesting about the kind of film you're not going to make. But we stuck to our guns. Of course, the streets aren't entirely empty of cars. And in a more realistic Wales, you would think `Why hasn't Boyo got a second-hand computer? Why isn't he on the Internet?' We create a world where those questions are not relevant."

Given the paucity of Welsh films, was there any pressure to somehow speak for the entire country? "Because it's set in Wales and we haven't got that many films, we're sort of inventing our own cinema at the moment," he says. "But House of America represents us, not a nation. If you're American, you have so many images of yourself to play with - the language is familiar. Coming from a country like Wales, you haven't got that, which is actually very exciting. You make your own language. Obviously it's almost incumbent on you to rattle the establishment of your home country but I'd like to achieve more than that. In my twenties, I spent too much time sitting in pubs moaning about the predominant Welsh culture. In your thirties, you become more complicated. You have to work out your feelings about home, and how to make them interesting to the outside world."

Evans first saw the original play of House of America eight years ago. It was a very personal project for its writer, Edward Thomas, who has also written the film's screenplay. Thomas had spent some time bashing out poetry, attempting to be cool and generally transforming himself into a modern Beat hero on the streets of Brixton. Well, it's as good a place as any. He realised that his poems weren't much cop after all, and turned instead to writing about his condition as a Kerouac casualty, which is where the character of Sid comes from.

"When I saw the play, I was very much like Boyo, Mr Let's-Keep-It-Together, rather than Sid, who wants to escape," Evans recalls. "It really comes down to Boyo vs Sid, that's the split you have as a teenager. It's about leaving vs longing. A Scottish priest once told me that there are two kinds of Celtic songs - the kind about people who leave for America, and the kind about people who get as far as the end of the jetty.

"I'm probably as much in the longing camp as the leaving one. I live in London, but still visit Wales. And yet my relationship with home only came into focus with the Devolution thing, when I realised that I didn't have a vote. I stayed up all night watching the votes come in on the telly, seeing people I knew getting drunk as skunks. If felt like an outsider, nose pressed against the glass and all that. And I realised by accident that I had already made that journey away from home.

"John Cale scored the film for us, and when I visited his home in Greenwich Village, he had a picture of Dylan Thomas on one wall and a huge lithograph by Roy Lichtenstein on the opposite wall, signed `To John from Roy'. I just thought: here is a man who has come from this place and gone to that place. That's the journey right there."

If House of America's intoxicating brew of the pungent and the lyrical strongly suggests to you that British cinema has an important new poet in its midst, then your faith is unequivocally vindicated by Evans's second film, which will be released before you've had time to recover from his first. Resurrection Man is set in 1970s Belfast, and traces the moral disintegration of a journalist who eagerly reports every swish of the Stanley knives that a trio of vicious young killers use to shred their victims.

It is a bleak, brutal but wholly responsible film, in which the streets of Belfast are transformed into a mythical battleground which calls to mind Angels With Dirty Faces or The Warriors. It's stunningly photographed in a mixture of greys and garish comic-book colours by Pierre Aim (who shot House of America and Mathieu Kassovitz's La Haine) and features what will surely turn out to be the most chilling cinematic joke of next year: "Tiger Feet" by Mud playing on a pub jukebox as a man is kicked to death. Bring your sick-bag along with your thinking cap. You'll need both.

"You can't get away from the politics," Evans shrugs, "but it is primarily a thriller. I just hope it will be discussed as much for its portrayal of the relationship between men and violence as for the political content."

Four months before its release, Resurrection Man has already attracted more than its share of acclaim and notoriety, but Evans is taking it all in his stride, assuming the traditional rabbit-caught-in-the-headlights demeanour that is part and parcel of being a young director with the world at your feet.

"I'm in a strange situation. I've got two films coming out within months of each other. And neither of them are musical comedies."

He chuckles, perhaps realising that he's just made the understatement of the year.

`House of America' is released next Friday. `Resurrection Man' is showing in the London Film Festival on 21 November (tickets: 0171-420 1122) and is scheduled for release next February