Jennifer Ellison is best known for parading her ample assets in a series of lads' mag photoshoots and causing a surge of young male viewers for the now defunct Liverpudlian soap Brookside. Andy Serkis is more familiar with the less glamorous climes of Middle Earth, gaining countless plaudits for his stunning turn as Gollum in the Lord Of The Rings trilogy. The pair join forces on the superb new British horror comedy The Cottage, with Serkis playing a wannabe gangster and Ellison his headbutting, expletive-laden hostage. We caught up with them in the swanky Soho Hotel for a chat.

Andy, what was the biggest challenge you found while making The Cottage?
Andy Serkis: "When I first read the script... I just thought it was brilliantly written and a great character piece. With the things that happened, you cared about the characters and it didn't feel like necessarily like a horror film. It felt like it was a real film with real events happening to real people. The biggest challenge when we came to shooting was to keep that a straight arrow and allow the comedy to come out of the emotional truth of the relationship of the characters... and yet appealing to the horror fans and fans of the different genres."

Did you have long to build a chemistry with your on-screen brother Reece Shearsmith?
AS: "That was the thing we worked on most - the relationship of the brothers. That, for me, was the most important thing to get right, to have that as the backbone of the piece so that everything else, no matter how extreme, still has that ring of truth about it. You back the characters, although they are despicable and what they are doing isn't right, you still care for their fates."

Jennifer, your character is very independent, foul-mouthed and a refreshing change from the usual scream queens. How did you find playing Tracey?
Jennifer Ellison: "It was so funny because my mum, my nan and everyone came to a viewing in Liverpool and I had to introduce the film and say quickly: “I apologise for the language. Please understand,” and then I kind of pointed to Paul [Andrew Williams, director] and said: “It’s his fault!” But it’s a part that you play and when I read the script I thought Tracey’s character was just so strong and really feisty and actually quite vile. It’s a lot different from anything I’ve done before, like Phantom [Of The Opera], and it's a great opportunity for me. It’s my first lead in a film."

Did you deliberately choose an unglamorous role to make a conscious departure from your sexy public image?
JE: "Not really. The script came five years ago and I'd just finished Phantom. I just loved the character. It was a great script. It wasn't anything that I decided to do or focus on. That was what came along really... the only reason that this film happened was because [Paul Andrew Williams] went away and made London To Brighton, borrowed the money and it won all the awards. There's a lot of directors out there who can't get the funding for British films. I've been cast in about eight, so it's just literally the British film industry."

Did you both find the night shoots quite hard?
JE: "Yeah, when you're going to work all your family is asleep. You feel so isolated and you start going a bit doolally. With the first night we were going home and there was this light and people were going to work and you feel like some drug addict... and all the crew were going in the bar!"

AS: "It was challenging in that a lot of the first part of the film had a lot of very heavy dialogue scenes between Reece and I that Paul wanted to shoot in one... so at four o'clock in the morning when you're remembering seven pages of dialogue and trying to get the timing absolutely spot on for the camera, for yourself, for the other person - that was quite challenging and taxing. But in terms of fun, we had a brilliant laugh doing it and it was a great crew. the weather on the Isle of Man was thankfully great and we had a really good laugh making it."

Andy, you've played your fair share of creatures in the past. Did you feel much sympathy for the guy buried under all the prosthetic make-up who played The Farmer?
AS: "He found it really hard. He's an actor but also a cage fighter as well. He wasn't used to the make-up process, sitting in a chair for hours on end and having that stuff put on. Like you say, I've done a fair amount of that stuff, and I remember when we did Lord Of The Rings that the transformation sequence of me to Gollum was a 19 hour make-up job. You have to have a kind of Zen button that you press and allow your mind to focus in a particular way. I know he was struggling with the hour and a half that he had... but you get used to that sort of stuff. It was particularly hard for him because it was all night shoots.

"I find The Farmer a really tragic character, although he's the monster of the movie. There's still an element of him being this childlike, psychologically mashed-up, disfigured animal. What life has he got? Even with The Farmer you're encouraged not to be judgmental in a strange sort of way."

Is it true you're working with Peter Jackson again on a movie version of Tintin?
AS: "Yeah, I'm flying out tomorrow to start Tintin. Steven Spielberg is directing the first one and Peter Jackson is doing the second one. We've got a little bit of shooting now, but the bulk of the shoot starts in September. That's just the way things worked out this with the writers' strike, things got moved around a bit."

Given that you've played Gollum and King Kong, were you worried when Peter Jackson got in touch with you about the upcoming Tintin movie that he'd want you to play Snowy the dog?
AS: "[Laughs] Absolutely! In fact people assume I am playing him! It's a bit disturbing!"

The Cottage is released in the UK on Friday, March 14

> Click here for our review of The Cottage