Marvel at the Fantastic Four

The Billy Elliot star plays Ben Grimm in the new Marvel movie, about four young outsiders whose physical forms are drastically altered after a teleporting experiment goes wrong.

And while the other characters' new-found powers range from being able to stretch limbs into extraordinary shapes to becoming invisible, poor Ben is transformed into a 6ft 8in, 1000lbs creature, whose entire body is covered in rock.

"I think Ben gets the worst of it," says Bell, 29, whose County Durham accent has softened slightly after years of working the US. "He has the worst affliction - he's literally a rock with eyes. Ben is so far removed from human form; he becomes something else entirely."

The film is a contemporary re-imaging of Marvel's original and longest-running superhero team - who first appeared in comic form in 1961 - and focuses on the quartet before they become a fully-fledged team.

Bell is joined on screen by Miles Teller (star of last year's Oscar-winning indie film Whiplash) as Reed Richards, the young inventor who designs a transportation device, The Wire's Michael B. Jordan as scientist's son Johnny Storm, and House Of Cards actress Kate Mara, as Johnny's adopted sister Sue.

It's not the first time the hugely popular Fantastic Four have been portrayed on screen, with various animated TV series and film adaptations in 1994 and 2005.

"I know Fantastic Four is a lot of people's favourite comic, because they're the first superheroes to really have problems. They're the most human of all of them," says Teller, 28, who plays leader of the pack Reed.

The actor, who previously appeared alongside Jordan in the 2014 comedy That Awkward Moment, enjoyed depicting Reed as a young man, rather than the big-time hero he goes on to become.

"I get to play a character that everybody knows from a certain stage in his life, and take him back 20 years before," he notes.

"What I really like about Reed is his focus and hyper-intelligence. I think being the smartest person in the room is a great asset. That's a lot of power. But when you're that smart, there are few people who can understand you, and so I just liked playing somebody a little more inside himself."

After the teleportation accident, when the quartet has discovered their powers - with Reed able to stretch to incredible lengths and morph into other guises, Johnny transformed into a human fireball, and Sue able to render herself invisible and create super-strong force fields - they must harness their new skills and fight a former friend-turned-foe.

For self-confessed "comic book nerd" Jordan, Fantastic Four was a dream gig. And like Teller, the human side of the tale was a big draw for him.

"It's just so relatable; you care about the characters," says Jordan, who is also 28. "For me, Johnny Storm is The One. He's charismatic and very passionate about life. He's optimistic and wants to be taken very seriously, but he has a light-hearted nature about him, so there's a balance."

While Johnny Storm adapts to his new status as a 'human torch' quickly, his hyper-intelligent sister Sue, like Ben, struggles to come to terms with her new powers.

"Obtaining them feels as if she has lost a limb," explains 32-year-old Mara, sister of The Girl With The Dragon Tattoo star, Rooney.

"Josh [Trank, Fantastic Four's director] wanted it to be clear that what Sue can do with her powers does not come easily. It's exhausting, mentally and physically. It's as if to go invisible or use her force field would feel like running a marathon, or holding my breath for an inhuman amount of time.

"Sue doesn't feel normal and just wants things to go back to the way they were," she adds. "Having powers she can't control is terrifying at first, and completely isolating."

Despite this emphasis on realistic, relatable, complex characters, there are plenty of special effects and stunts to keep cinemagoers on their toes too.

For his role as flying fireball Johnny, Jordan was required to wear an interactive fire-light suit, fitted with hundreds of pulsating yellow and orange lights (with CGI finishing touches added later).

Bell, meanwhile, donned special stunt stilts, to add an extra foot of height to Ben.

"I didn't know they were going to ask me to do that," he admits, laughing. "But it was fun, it really was. I think it hopefully helped these guys [Bell's co-stars] imagine somewhat what it would be like to be with Ben."

Bell's dance background also helped him convey Ben's new-found height and bulk, but he confesses that the stilt work wasn't rocket science.

"I would like to say it took hours and hours and hours of work, and it was really complicated and really added to my craft and made me a better actor," he says with a smile.

"But the truth is, any layman could really get on them and waltz within an hour."

:: Fantastic Four is released on Thursday, August 6