Ioan Gruffudd is perfect. No, really. Leaning rakishly against a corner table of a swank London eatery, the 33-year-old Welsh-born actor and star of the 18th-century political drama Amazing Grace ( see review, page 16) is an impeccable vision of Young Hollywood in the making. His eyes smoulder, his voice is a caramel burr, while his lightly tanned face has a pristine sheen of well-tended beauty.

“I love the mantle of the leading man,” he says, wistfully, with a touching lack of hubris. “I’d love to be a Cary Grant or a Gregory Peck.”

A fanciful plan? Maybe not. For thanks to the $330 million box-office haul of his last blockbusting movie, Fantastic Four, the former teenage oboe-player from Cardiff has suddenly become white-hot property in Tinseltown. His meaty role as the laudanum-addicted and colitis-afflicted abolitionist William Wilberforce in Amazing Grace will thus be followed by the soap-opera satire The TV Set, plus another outing as the rubber-limbed Mr Fantastic in the Fantastic Four sequel: Rise of the Silver Surferthis summer.

He says that it’s a dizzy time for him right now, and that it’s all about balancing the blockbusters with serious character work such as Wilberforce. Tackling that role, he says, was an actor’s dream. “You read the script and you see the laudanum addiction, and the colitis and you think, ‘Yes! At last – something I can get my teeth into!’ Because most of the characters I’ve played so far have been very heroic and very physical. Here, finally, was someone who didn’t look great and handsome all the time.”

Consequently, his Wilber force, when not valiantly battling the proslavery interests in the House of Commons, spends much of his screen time either doubled over in agony, or lying in a sweaty, cadaverous heap next to the fire. “Yes, he was addicted to laudanum,” Gruffudd says. “But he was such a disciplinarian that he was able to take just the right amount of dosage to suppress the pain of colitis and to function at the same time.”

Unsurprisingly, Amazing Grace, together with his studio smashes, has created for Gruffudd the kind of industry buzz, complete with action figures, LA homestead and chat-show rotations, that would make other wannabe Brit-stars foam at the mouth. But he isn’t gloating. Instead, he has advice for his home-loving hipster peers: stop fooling yourself with antiHollywood cynicism. Go on, he says with proselytising zeal, live the dream!

“I would say to all other British actors: ‘Please don’t tell me that you haven’t once stood in front of the mirror and quoted Scarface or The Godfather, or made your Oscar speech!’ The only difference with me is that I admitted it; I said I wanted it, and I broke the taboo.”

His Hollywood dream began in 2002 when he moved to LA with his 102 Dalmatians co-star, and now fiancée, Alice Evans. There the emphasis on stardom and business mores appealed to Gruffudd, who claims to be unconcerned with the deeper machinations of the acting Method. “There’s no real method to my acting,” he says. “It’s instinctive. I don’t need to prove myself as an actor.”

Gruffudd’s brooding looks and six-year stint as a swash-buckling hero on TV’s Hornblower proved an effective calling card, and movie offers followed (see his Lancelot in King Arthur). The lifestyle too suited the new arrivals, and Gruffudd, a former self-confessed Kilburn party animal, says that now he likes nothing better than to read scripts in the sun, swim, eat vegetables and baked fish, and wear an orthodontal retainer in bed at night.

“I’m unashamed of it,” he says, beaming. “I realised around the time of King Arthur that this is a business, and my livelihood. I want to savour it. I can’t drink until dawn, go to work and just survive the day. I want to experience the day.”

Gruffudd says that the Americans appreciate his upbeat attitude, and like to hear about his past work, from the Welsh language Solomon and Gaenor right through to smaller roles in Titanic and Black Hawk Down. In person, he is resolutely charming and impossibly nice, and has a great reverence for his co-stars. Working with Albert Finney on Amazing Grace, for instance, “wasn’t just a lesson in acting, but a lesson in humanity”.

And yet, is there a possibility that Gruffudd might be too perfect? Surely he has a dark side? He thinks for a moment and confesses: “I’m one of those people who’ll suppress things and suppress things. Then one day, bang! The fuse will blow and I’ll start hitting inanimate objects.” He adds, however, that he doesn’t hit them hard enough to break them.

In the meantime there’s a gruelling Fantastic Four publicity tour coming up, which for Gruffudd means battles with persistently hysterical mobs of screaming fans. Not that this bothers him in the slightest. “I absolutely love it,” he says, his beatific smile beaming widely again. “It’s an incredibly flattering and gratifying experience. There’s nothing quite like the face of a child whose eyes are filled with wonderment when they meet you. It’s just priceless.”

As I say. Perfect.

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