This little piggy...

It has won Britain's most prestigious young playwright's award (the George Devine), stormed Dublin, and was just about the only theatrical "discovery" at a quiet Edinburgh festival. Tonight it makes a triumphant transfer to London's Bush theatre. For a play in which it's impossible to follow 60 per cent of the dialogue, Disco Pigs has had extraordinary success.

Despite being priced at pounds 6.99, texts of the play swiftly sold out during its run at Edinburgh's Traverse theatre, snapped up by an audience that was as beguiled as it was banjaxed by Enda Walsh's tale of two adolescents on the rampage in Cork. His play's thick Irish accents, baby language, rap talk and loud funky soundtrack create an effect that's often more musical than verbal.

Even audiences in Cork City have been hard pressed to understand the language. Disco Pigs doesn't quite bludgeon the ear - it's too lyrical for that - but it gives no favours to the lazy or inebriated watcher. And, in Edinburgh, where as often as not audiences are inebriated, that meant a guaranteed couple of walkouts per performance.

The play has been hyped by the press like nothing on stage since Mark Ravenhill's Shopping and Fucking. Meanwhile, critics have carelessly drawn comparisons with Trainspotting and A Clockwork Orange, analogies that acknowledge the vibrancy of the play's dialect but miss how soft-hearted and tender it is. For all its teenage protagonists' hormone-fuelled bluster, for all their threats to "kill the town", Disco Pigs is a very simple love story.

Born within one second of each other and inseparable throughout childhood, the boy Pig and the girl Runt celebrate their 17th birthday by going on a drunken rampage through Pork Sity, a fictional version of Cork. These are the two "disco pigs" of the title. "That's a phrase I made up," says Walsh. "A disco pig is a person who completely isolates himself or herself and begins to look at things from a distance. They mutter and whisper. It's an extremely Irish thing. People say, `See that ole bitch over there!' or `Have you heard about so and so?' I spend a lot of time in burger bars. I love them. And those places are just full of disco pigs, usually in pairs. Murmuring to themselves. Looking miserable. In the play, what Pig and Runt have to say about everyone else is very immature but very smart and funky."

The pair wreak havoc at a student club, at a pub full of karaoke-singing provos and finally at a huge, almost mystically alluring, white nightclub by the sea. They scrap with and bitch about the people they encounter on their picaresque night out. They talk about what the "colour of love" is. Pig yearns sexually for Runt. Runt yearns for a life beyond this smalltown existence of beering and sneering, and yet she can hardly express what it is.

In Patrick Kiernan's dazzlingly well acted production for Cork's Corcadorca company, the pair oink their way around inside a pig pen with increasing desperation. They may be portraits of snarling youth, but they're as vulnerable as a pair of piglets.

The most likeable aspect of Disco Pigs is how full of undiluted adolescent emotion it is, how completely engrossed it is in the claustrophobic world of being a teenager. It's no surprise to discover the script was written in a mere two and a half weeks, then workshopped with the actors: it feels like something that's been banged out furiously.

The play was inspired by a dream. "There were these two huge pigs walking through Cork, picking up the General Post Office and eating it, and it being shat out of their bums," Walsh says. The finished product retains a dreamy, loose-structured feel. Walsh never analyses his characters' plights, nor is he concerned with what Pig and Runt ought to do. If you were being dismissive, you would accuse Disco Pigs of wallowing in unexamined emotion. It does. But seldom does a play wallow so flamboyantly.

The author himself is no teen sensation, even if, with his boyish crop, Bambi gaze and Walkman, Walsh could pass for 20. In fact, he's 30, with an adaptation of A Christmas Carol and a play about a ventriloquist growing up on a Cork housing estate to his name. "But I was feeling like a 17- year-old when I wrote Disco Pigs last year," he explains. "I had this awful relationship with a girl at the time. A lot of writing Disco Pigs was to do with exorcising that.

"I mean, emotionally you don't develop that much between 17 and 28. I love the directness of those young characters. They're trying but failing to articulate themselves brilliantly, then they finally say something that makes sense but is very simple."

And simple is how Walsh wants to keep it, despite attempts to add his name to the list of hip young Irish writers currently dominating London stages. "I know they're the thing. But I don't want to be a thing. I don't want to live in London. And," he adds, "I don't want to have plays in the West End." On current form, that may be more of a problem than he thinks

`Disco Pigs' previews at the Bush theatre, London W12 (0181-743 3388) from tonight