Guy Pearce is manacled, and hanging upside down in a giant glass water tank on a soundstage in Ealing Studios. The cameras are rolling on the Houdini movie Death Defying Acts, but the producers, the insurance agents and the safety men are panicking. They know that their 39-year-old Australian star has been training with free-diving record holders for weeks now, and that he can hold his breath for nearly three minutes (the record holders manage nine). And they also know that the scene is the only traditional Houdini set-piece in a film that will otherwise dwell on the cat’n’mouse intrigue between Houdini and a phoney stage psychic called Mary McGarvie, played by Catherine Zeta-Jones (she wants his money, he wants to expose her – they’re a perfect match). But still, anything can happen in these conditions, and if they lose their leading man, they’re screwed.

“They’re running around shouting, ‘Pull him up! Pull him up!’ ” chuckles Pearce, recalling the incident, curled up barefoot on a large leather sofa, in a swish Central London hotel room. “But, ironically, I found it to be a very peaceful place.” The actor, in person, is breathtakingly handsome, far more so than he has ever appeared on screen. His face is smooth-featured and almond-eyed; on film, in everything from LA Confidential to Factory Girl, he can seem angular and severe. Or maybe it’s just his demeanour? For he is also impossibly relaxed and unguarded – again the complete opposite of his brittle screen persona (think of the fragile amnesiac Leonard in Memento) and, more importantly, the opposite too of the angst-ridden neurotic that, he admits, he used to be until very recently.

So what’s changed? Why has he mellowed so profoundly? And why has an actor famed for his perfectionism and for being ruthlessly selective about his roles (often making only one film every two years), suddenly found himself with eight new movies – yes, eight – coming out over the next 12 months?

For the answers, we have to go back to the tank. “I definitely had ‘wow’ moments where I thought about dad while hanging upside down in that tank,” he says, referring to his father, Stuart. He was an air force pilot who died in a test crash in Melbourne when Pearce was only 8. Stuart was 39, and the tragedy had a profound effect on the son, instilling in him debilitating levels of anxiety and imbuing the age 39 with a heavy, and perhaps undue, significance. “All my life I’ve wondered about being 39,” Pearce says. “I had tried to understand my dad, and how, for a few seconds at least, here was a man who knew that he was about to die. What the f*** does that do to you? I thought, ‘When I’m 39, will I have a clearer understanding of who he was, or will I just revel in the knowledge that it doesn’t mean anything at all?’ ”

Thankfully Pearce, who turned 39 on the set, realised right there, in the tank, and underwater, that it didn’t mean anything at all, and that, in some ways, he was free from a lifelong curse. It was a benign topper to a mellowing process that was already under way, he says. He believes the new Pearce is far less precious and less obsessive, and has fun with his craft. He ruminates aloud, for instance, about kissing Zeta-Jones in Death Defying Acts. “She was lovely, but you can’t help thinking, ‘Am I going to be there on opening night with the husband going [makes crazy face and points finger], You!’ Although Michael Douglas seems pretty confident.” He jokes about his role as an FBI enforcer in the thriller Traitor. “I basically play a block of wood,” he says, laughing at his own inadequacies. On his forthcoming Adam Sandler comedy Bedtime Stories, he muses: “I never would’ve done an Adam Sandler movie five years ago. But I’m much better at dealing with all that stuff now.”

The pre-tank Pearce was a different story. As a child, an only boy, who had to be the man of the house for his handicapped sister Tracy, and his mother Julia (a teacher originally from Durham), he took acting, his only escape, very seriously indeed. He turned himself from an adolescent weakling into a rippling Mr Junior Victoria (he liked pumping iron because he could be alone), and moved quickly from local theatre to a starring role in Neighboursas the diver Mike Young. Even at this stage, at barely 20, he despised anything other than “the work”. “I used to struggle with the media attention when we did Neighbours,” he says, referring to the Kylie-and-Jason hysteria that dominated the show’s high period. “I could see it around me, and I didn’t want any of that s***.”

When he segued into movies, with The Adventures of Priscilla, Queen of the Desert; LA Confidential and Memento, he was equally stringent with himself, often with mesmerising results. His Ed Exley in LA Confidential is both the perfect foil to his hot-headed co-star, Russell Crowe, and a fascinating study of self-control. Or there’s Leonard in Memento, flickering rapidly between comic confusion and fearsome purpose.

The industry, however, pushed Pearce into blockbusting stinkers such as The Count of Monte Cristo and The Time Machine. He clashed badly with the suits who demanded reshoots and plot changes. On The Time Machine, his protests were silenced by a studio executive declaring: “The machine is the star of this movie!” After that, he says, there was nowhere to go but down. He effectively fled from the business, hired a beach hut in the Australian NorthWest and zoned out. “I decided I wanted to give it all up,” he says. “I was sick of the industry and the pressure and all that crazy stuff. I was having a really difficult time and smoking way too much dope.” He says that nonetheless, over time, he pulled himself back from the brink, gave up the dope and realised that he still had an interest in acting. He was reinvigorated by the lead role in John Hillcoat’s stunningly bleak Australian western The Proposition. It was a part of a process of rejuvenation which culminated in the water tank in Ealing Studios.

He says that he has no regrets about his past, or about why he didn’t become as big as that brawling bad-boy Russell Crowe. “I admire Russell’s talent, and I’m envious of it,” he says. “But I don’t admire the attention he gets. Although I think he brings some of that s*** upon himself.” He says that the mogul Harvey Weinstein regularly chastises him for not being starry enough. “He says to me, ‘When are you going to do a movie that someone is going to f***ing see!?’ ” Pearce says. “And I say, ‘Well I get to do good work, I get paid, and I maintain my privacy.’ ” Pearce’s privacy revolves around his 11-year marriage to the psychologist Kate Mestitz.

The Melbourne-based pair are childhood sweethearts who drifted apart but were reunited early in Pearce’s acting career. He once made the mistake of claiming, on the record, that they were a brooding, boring couple. “We are not at all!” he says today, cringing and adding: “She really told me off for saying that.” He jokes some more, about future movies, about being offered the role of James Bond (“It never happened!”), and even about why he and Kate refuse to have children. “We’d be on the news if we had kids,” he says, giddily. “We’d do something horrible to them or leave them somewhere.” He pauses and for the first time a shadow crosses his features. “No,” he says, seriously, “I shouldn’t say that we’d do horrible things to them. I just mean that, well, I couldn’t give them the constant love that they need.” He pauses again. More flickers of gloom. Maybe it was the child thing? You wonder are you losing him. You want to tell him, No! Stay away from the dark, Guy! It’s not worth it! Remember the tank! Remember the tank!

Death Defying Acts is out on Friday 8 Aug 2008

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