Joseph Gordon-Levitt has a rebellious streak.

The 'Walk' star, who plays a real-life acrobat Philippe Petit in the new film about his famous wire walk between the Twin Towers of the World Trade Centre in 1974, has never been been in trouble with the law, but likes to break with convention.

The 34-year-old star said: ''I've never really broken the law much, and I've never been arrested, but I think as far as rebelling against convention - even this movie is sort of a rebellious movie.

''It's a grand-scale action movie, but there's not shooting, there's no killing, there are no explosions. These are typically the hallmarks of big action movies coming out of Hollywood. When you do something different than the norm, it's risky.''

Joseph relished the opportunity to get insanely fit for the film.

He told Us Weekly: ''Wire walkers are actually in great shape. It's very physically strenuous because your whole body has to be tight. If anything is loose, you flop over and lose your balance. And I was eating really healthy. I cut out sugar and added a lot of vegetables.''

The actor worked with Philippe for just eight days before walking on the wire by himself for the first time.

He said: ''I thought that sounded ambitious, but he was so thoroughly convinced that I was going to be able to do it that he made me believe. And he was right!

''You'd be surprised how high it feels when you're actually up there.''