What an entrance! Two giant doors swing open, jaws drop, mouths gasp, and in he marches, in thick dark overcoat and darker hypnotic glare, leading an equally swarthy bunch of rugged youths. “Please welcome,” announces a tremulous Professor Dumbledore, “the proud sons of Durmstrang!” Yet all eyes are on him, at the head of the pack. He’s a champion sportsman and a smouldering suitor, and his name is Viktor Krum. And with his shaven head, shadowy goatee and killer cheekbones, he positively reeks of unfettered machismo. Which, when you think about it, is quite something for a Harry Potter movie.

“That manliness is important,” admits Krum’s off-screen alter-ego, the 20-year-old Bulgarian Stanislav Ianevski, when contemplating his grand entrance into the new hormone-addled Harry Potter and the Goblet of Fire. “Viktor Krum has to be powerful. So I tried to bring him alive in such a way that will make an impact right from the very beginning. You want to see that power the moment he walks in.” And we do. Ianevski’s raw masculinity not only hints at the emergence of a highly watchable performing powerhouse, but also provides an invaluable Slavic edge to a franchise that occasionally veers into twee Anglo Saxon infantilism.

Today, however, Ianevksi’s manly power is firing only on half cylinders. Battered by a severe winter flu, he lies low in the house that he shares with his parents and 16-year-old sister in suburban Sofia, and watches sporadic bouts of Eurosport in between regular interviews with Bulgarian journalists. The flu has also forced him out of the New York Potter premiere, but he’s not bitter. Instead he has had time to reflect on his dizzying transition from anonymous long-distance boarder at a posh North London school to the hottest new member of a globally insatiable billion-dollar movie-making phenomenon.

He explains, with the endearing swagger of a young Bulgarian Brando, that he never wanted Potter in the first place. Just happened to be outside the headmaster’s office (Late again, Ianevski?!) when the movie’s casting director, Fiona Weir, popped by for a cattle call. Ianevski, who had no acting experience and wasn’t even one of the school’s drama students, reluctantly auditioned for Weir.

He then proceeded to ignore two coveted call-back requests and, only after some haranguing phone-calls, decided to attend a third audition where he met the director, Mike Newell, and bagged the part of the Bulgarian quidditch king Viktor Krum.

“After that, everyone in school went mad,” he says. “Like, ‘Oh my God! I’m going to take pictures of you and sell them on eBay!’ The teachers were complaining about me missing lessons and study for my A-levels, but I was like, ‘Hey, I’m feeling good, so why does it matter?’ ”

Ianevski traces his thespian genes from his Soviet-era actress grandmother and his once-professional ballerina mother (both his parents are now Bulgarian-based business people), but says that his approach on set was always about casual realism. Certainly his performance is the least mannered among the film’s junior players. Elsewhere, his surly, simmering machismo is less feigned than the casual viewer might imagine.

“Thing about me,” he begins, with typically disarming candour, “is that I’m quite well-built. I train a lot, too, so people often get the wrong idea about me, even in real life, like, ‘Oh my God, this guy is big — stay away from him!’ But then once they get to know me it’s completely different.”

What, you’re a softie on the inside?

“Not really. I’m a Taurus.”

What does that mean? “It’s like bulls. You can make them angry. They’re relaxed normally, but once you cross the line there is no way back.”

And what do you do when someone crosses your line?

“I go training. I can’t hold all that power inside!” Ianevski’s training routine must be at Olympian levels these days, considering the number of lines that have been crossed by the media since his sudden ascension into Potter heaven. In Bulgaria the press attention has been particularly relentless, and yet the fiery Taurean has greeted it all with surprising equanimity.

“Even in the paper today there was a thing about me. Apparently, I hate Bulgaria and it’s a real ordeal for me to attend the Bulgarian premiere (which Newell is flying in for). It’s complete rubbish.

“Or there was another one saying that I’ve had this black girlfriend for a year and we have a really active sex life. I don’t take it seriously. My Mum does, but I don’t. I’m like, ‘Let them write it!’

“And that’s the thing — you can never really be prepared for this. But I could have turned down the role, and I didn’t. So that means, in a way, I’ve signed up for this. It was my choice.”

As regards romance, Ianevski is quick too to quash any would-be-rumours about raunchy off-camera action with his onscreen love interest Emma Watson. “There wasn’t really time for that sort of stuff,” he insists. “When we were working on the film we were really just concentrating on that.”

He adds that even right now, from his sickbed, he’s not sure that he wants to be troubled with a full-time paramour. “Sometimes, when I want hugs and stuff, I just really want to be with a girl. You know what I mean? But it all depends on chemistry and hormones.”

In the meantime there’s the future to think about. And Ianevski is thinking big. As usual, and with his now alarming enthusiasm, he explains how, with big-name star brands as role models, he hopes to parlay a successful acting career into nothing less than the creation of a self-made merchandising phenomenon.

“Look at all the big celebrities, like David Beckham, Jennifer Lopez and Britney Spears! They’ve all made their own fashion lines and perfume. I’m hoping to do that as well, one day.”

It’s official. Stanislav for Men. You smelt it here first.

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