When a foul-mouthed movie king took on the Bard, purists wailed. They'll cheer yet.
It's enough to make a grown academic weep. The actor-playwright renowned for his appetite for swearing, bad behaviour and in-yer-face theatre has had a go at that most delicate of verse forms, the Shakespearean sonnet. Eric Bogosian, best known as Barry Champion, shockjock supreme, in Talk Radio, the Oliver Stone movie of his hit stageplay, is to decorum what Ruby Wax is to discretion. The last person in the world, you might think, who should be encouraged to go anywhere near the Bard.

Purists will shudder at his description of looking up "Sonnet 118" last year: "I had to re-read it several times to figure it out. All I could grasp was that there was something about poison. I sensed that there was a major brain here trying to explain something very complicated." The lines he puzzled over most were those fiendish tongue-twisters: "Even so, being full of your ne'er-cloying sweetness, / To bitter sauces did I frame my feeding".

They provided him with his title. Bitter Sauce opens at the Barbican tonight as part of a sonnet-themed showcase of new US writing called "Love's Fire", commissioned and performed by The Acting Company, the country's leading professional touring group. They also pointed the way to a dramatic moment, a heightened attitude. Bogosian explains: "This is about a person cheating on their loved one, then trying to rationalise it in a very twisted way. The argument runs: 'Things are so overwhelmingly good between us, that I needed the bitter sauce of an affair to prevent them from becoming too good.' I don't think many people would buy that, but in the heart it sort of makes sense."

Although several of the six other plays are strikingly contemporary (Wendy Wasserstein's Waiting for Philip Glass is set at a chic benefit in the Hamptons; Tony Kushner's Terminating is a dialogue between a young man and his female psychiatrist - it is Bogosian who goes all out for modern day manners and mores. His heroine, Rengin, tells her fiance that she has been seeing a 180lb Hell's Angel on the sly: "an animal - the kind of guy who starts fights and hopes that the cops show up so he can fight them, too". Shakespeare's "policy in love" has become a Nineties emotional insurance scam: "I was in this bar one night, getting shit-faced because I was so in love with you..." Rengin starts to confess, on the eve of her wedding.

Those who have seen Bogosian's other work, in particular anything from the vast back-catalogue of rolling monologues, will know the score. Dialogue so crude it sounds as though it's improvised, an air of violence and a sense of incompletion, as though the playwright had given up a minute too soon. Bitter Sauce provides an ideal crash course in the motormouth's oeuvre. "I don't know whether it reaches the level of drama," Bogosian drawls down the line from his New York office. "It's sketchlike, which is the way I want to write. I'm not trying to write deeply complex characters, I'm trying to write the characters who live inside my head."

His random bursts from the discontented depths of his nation's psyche have tickled and terrorised audiences over the past two decades. Seemingly everyone, from the desperate street bum to the self-satisfied millionaire, has walked the gangplank of his theatrical imagination. When he last came over to perform, in 1994 at the Almeida, liberal Islington was pummelled with extracts from Pounding Nails in the Floor with my Forehead (Sample line: "Right now as I say these words, somewhere in Africa, there is a vast sea of human beings slowly starving to death! Starving Africans! They spoil everything!'')

Where other writers crave subtext, Bogosian prefers full-on confrontation, letting the audience squirm in guilt and discomfort. He still dreams of making his work as pulse-quickening as the music of his teen heroes, Frank Zappa and Tom Waits. "I come from a non-literary background," he says, "a working-class suburb [Woburn, near Boston]. I grew up listening to records and watching TV, not seeing plays. I want the experience to be accessible to my life".

At 45, Bogosian runs the risk opounds sounding like an ageing hipster. In the late 1970s, the experimentation that followed drama school was extreme: smacked-up to the eyeballs, he would turn up in NY dives and "pick fights with the audience in character, it was wild". He acquired notoriety for himself over here during the early Eighties for going berserk during the Edinburgh Festival: wrecking a dressing room and a tractor that had been cheekily driven through the tent in which he was performing by the comedian Malcolm Hardee. "I kind of made an ass out of myself."

These days, he's a family man, with a wife and two kids. He cultivates his cool on the web, offering regular "meditations" and merchandise. He set up this electronic temple to himself just as he became a mainstream phenomenon. He is, he freely admits, Hollywood's rent-a-gob: "I get to do the monster monologue each time - there's no question that talking is my thing". He recently starred as the megalomaniac scientist Travis Dane, who wipes out China in Under Siege 2 and is currently to be seen prancing round in a yamaca in Deconstructing Harry ("My ancestors are Armenians, I was brought up Christian - but because I have the features of the classic American Jew, I'm becoming like this representation of Judaism in America now. It's very odd.")

His latest role is as Daniel Ellsberg in A Bright Shining Lie directed by Terry George (who wrote In the Name of the Father). "A man who almost single-handedly, and very courageously, brought an end to the Vietnam War by releasing secret government documents to the New York Times and the Washington Post."

The experience reradicalised him, he says. But don't go expecting any protest plays. He's following his last ensemble piece, Suburbia, the slice of slacker generation blues winningly filmed by Richard Linklater last year, with Griller - the tale of an out-of-control family barbecue. "I go wherever interests me," he says. 'I peer into my soul and my soul is suburban." Bogosian doesn't care who hears it, he's more Avon lady than Stratford-upon-Avon man.

'Love's Fire', 20 May to 6 June, Barbican Pit, Silk St, London EC2