Three years ago Robert Pattinson was a little-known actor with a small part in two Harry Potter films and a handful of TV roles behind him.
Fast forward to 2011 and the British actor – known as "R-Patz" to his devotees – can't even step out of his front door without feeling paranoid about being accosted and stalked by fans.
"A lot of the time you think people are way crazier than they are. You think they've been waiting for five hours when they've only been there for five minutes.
"I was in London once and no one found out where I was staying the whole time I was there, and then this girl, waiting in the courtyard of the hotel in complete pitch blackness, called out my name – and I thought, 'This is it. I'm going to get killed'," he says, grinning at the memory.
"The thing that drives me crazy is if people follow you when you leave the building. As soon as I lose those people, I'm fine."
The reason for all this fear? The film juggernaut that is The Twilight Saga, a spellbinding love triangle between vampire Edward Cullen, Bella Swan and werewolf Jacob Black.
Based on Stephanie Meyers' best-selling books, the three films, with the eagerly anticipated fourth instalment Breaking Dawn Part 1 about to hit screens, have propelled the lead cast members – Pattinson, Kristen Stewart and Taylor Lautner – to global stardom.
Running his fingers through his tousled hair, 25-year-old Pattinson says: "I just have to remember that it is all a job and that the craziness, as overwhelming as it seems sometimes, won't last forever."
It's little surprise that Pattinson, with his finely chiselled features and lean stature, has become such a heart- throb.
Yet fame has not gone to his head. The London-born actor, who now splits his time between the UK and the US, takes his new life in his stride.
"I guess my actual life hasn't changed that much – it's busier. The only time I found it really difficult to cope was when I tried to go to the same places I went to before, and live exactly the same life, and it's impossible," he admits.
"But life changes and you have to adapt to that. You can either let yourself go completely insane or just deal with it. My family and friends haven't been any different the entire time. It's lucky that I didn't do too much beforehand."
Shot back-to-back, the first of the final two Twilight films, with the second part to be released next November, sees Bella and Edward taking their relationship to the next level.
"Breaking Dawn begins with preparations for Bella and Edward's wedding and the chaos that ensues on their honeymoon, and the inevitable downfall that always happens in Twilight movies," says Pattinson.
"The wedding scene is a relatively momentous moment for the series. I think Edward's proposed to her about 50 times now, so it's been building up and building up.
"Edward's excited. He's always been obsessed about marriage. It's what he has wanted for a long time. I think it's one of the first points of stability in their relationship."
Their honeymoon on a beautiful island in Brazil "starts off quite nice and just gets progressively worse", reveals Pattinson.
"It just goes downhill after they have sex. Edward gets to relax – but only for a second. It's like a set-up so he can get punished again for the rest of the movie consistently."
Shooting the love scenes with Stewart, widely believed to be Pattinson's girlfriend, brought some pressure because of fans' expectations for the previously celibate on-screen couple.
Sighing, he says: "It's more an abstract idea of living up to expectations because you don't know what the expectations are. Especially with the honeymoon stuff, it's just in people's imaginations.
"You never really think about the reality of what people's expectations are, you just try and make it good. And if you like it, then hopefully other people will like it."
Trying to measure up to co-star Lautner, who has no qualms about appearing shirtless, required some dedication from Pattinson, who reportedly worked out for six months to get a six-pack.
When Bella unexpectedly falls pregnant with their half-human/half-vampire baby, their marriage suffers "a lot of strain" as Edward feels the baby is a death sentence for Bella, while she considers it a miracle.
But when Edward realises there's no changing Bella's mind about the child, he becomes more supportive.
To sustain the baby and herself through pregnancy, Bella has to drink blood which she then reacts to and throws up again. Pattinson says he "loved" doing the gruesome birth scene.
"It could have been an R-rated sequence – or a really ridiculous comedy sequence," he says, laughing.
"We kind of shot it as an adult horror and then edited out the really gruesome bits.
"It looked like a Saw movie, not a Twilight movie."
He adds: "There's literally been no blood in the films, except for single drops here and there. I walked in and Kristen was covered in fake blood and gore."
In between shooting the Twilight films, Pattinson has kept himself busy. He played Salvador Dali in Little Ashes, starred in tear-jerker Remember Me and romantic drama Water For Elephants.
Yet stepping back into Edward's shoes was easy. "You do feel Edward's back as soon as you go into make-up, for one thing, it's quite limiting. All of the limitations of the make-up, wardrobe and even the contact lenses, they all play into the character," he says.
Prior to Twilight, Pattinson's biggest role was as Hogwarts champion Cedric Diggory in Harry Potter and the Goblet of Fire, where he played second fiddle to the film's main stars Daniel Radcliffe, Emma Watson and Rupert Grint.
With the end of the Twilight franchise in sight, Pattinson has upcoming roles in David Cronenberg's Cosmopolis and period piece Bel Ami.
"I like working all the time," he says. "I spent so many years before Twilight just working for two to three months and then doing nothing, or these tiny jobs, for the rest of the year.
"That's the hardest thing to deal with. You're like, 'Ok, I'll just go get drunk again'."
See our review of The Twilight Saga: Breaking Dawn Part 1, below left.