Sienna Miller fights like a man in her new film.
The British actress claims she and co-star Rachel Nichols have a "brutal" brawl in the upcoming action movie 'G.I. Joe: Rise of Cobra'.
Sienna, 26, said: "Rachel and I have one of the toughest girl fights I think people will ever see. I mean, it's chains and it's brutal, nasty, dirty fighting - proper boy fighting, but between women."
Although little is known about the plot of the film - based on a comic and cartoon series made around G.I Joe action figurine toys - Rachel's character, Shana Scarlett' O'Hara, is one of the heroes, while Sienna plays lead villain The Baroness.
Sienna says she felt like a real baddie as soon as she was handed a deadly weapon.
She added to Total Film magazine: "I didn't feel like a big villain until I got my machine gun. But then I thought 'I can get into this!' The Baroness is fundamentally a villain, a femme fatale. A nasty piece of work."