Going up in the world: Nicholas Hoult

Nicholas Hoult is in between worlds right now. The 23-year-old British actor who shot to global fame as Hank McCoy (aka Beast) in X-Men: First Class is just back in London from Namibia. He has flown in for a brief meet-and-greet before heading back to Africa to complete filming of Mad Max: Fury Road, the long-awaited fourth instalment of George Miller's popular post-apocalyptic series.

Dressed in a maroon leather jacket, charcoal combat trousers and a grey T-shirt, Hoult walks into the hotel room and removes his baseball cap to reveal a skinhead cut. "People have a different response to you when your head is shaved," he says with a grin. Part of his guise for playing the warrior Nux in Mad Max, it looks severe: the cherubic lad with the pudding-bowl cut he so charmingly embodied in 2002's About a Boy is long gone.

It's also some way from his role in Bryan Singer's fantasy Jack the Giant Slayer. Hoult plays Jack, a farm hand who opens a gateway to a world of fearsome giants. So what's the appeal? "There's the romance and the adventure and the epic scale of it, and the world that you get taken into is really spectacular. But I think there is also humour and lightness to it. It's a good family romp," he says.

The movie is inspired by the Jack and the Beanstalk fairy tale - and for those craving overgrown vegetation, the film doesn't disappoint. "They built 50-foot-high pieces of beanstalk and then proceeded to throw water on us, and get these really powerful air cannons and spray us with those as well. We're just hanging on … these beanstalks, slipping around," Hoult says.

Shot two years ago, Jack the Giant Slayer was slated for release last summer but was delayed for nine months while Warner Brothers reportedly pumped more money into the special effects budget. Now it's one of this season's biggest releases, looking to do battle with Sam Raimi's Oz the Great and Powerful at the box office. Hoult is aware of the pressure on his young shoulders. "You're in the middle of what is costing a lot of money and you don't want to mess it up."