BEVERLY HILLS, California — This week, Sienna Miller stars in a World War II-era film about the doomed romances of Welsh poet Dylan Thomas. In August, she'll play the Baroness in the "G.I. Joe" movie.

We'll give you one guess which film plans to make action figures that resemble the 27-year-old beauty.

"I don't think anyone, anywhere would be playing with them," she laughed when imagining a toy line for "The Edge of Love," which casts her alongside Keira Knightley. "['G.I. Joe'] is a whole new experience. ... I'm not sure if I'm going to be playing with my own doll — but I'm going to have happy nieces and nephews, I'm sure."

Ever since we got our first peek at the big-budget "Rise of Cobra" during the Super Bowl, fans have been arguing over one scene in particular: footage of two figures in bodysuits, defying the laws of nature, as they catapult over rockets and jump through a speeding bus à la "Wanted." Who's in there? And what do they have to do with the Real American Heroes?

"I'm not inside one of them," Miller assured us, finally revealing the identity of the jumpers in the acceleration suits. "Channing Tatum [as Duke] and Marlon Wayans [as Ripcord] are in those in that scene. It's Channing and Marlon; they are [in] suits that make you run extremely fast.

"It's gadget heaven," Miller said of the flick, directed by "Mummy" filmmaker Stephen Sommers. "This movie is definitely taking effects to a whole new level. It's really, really exciting."

Sienna said her favorite scene, however, was decidedly low-tech, depicting her evil Cobra assassin pulling hair with Joe agent "Scarlett" O'Hara. "There's a really, really good girl fight between Rachel Nichols and myself," she explained. "It's like a proper, violent girl-fight scene. And we both worked so hard for the choreography and the training of it. ... We both got hurt. I'm clumsy, so I slipped on a rubber bullet at one point and sprained my wrist quite badly. She ran into a flame and got burned."

As for her leading men, Miller was eager to talk about one — but not so much about the other.

"He's great, he's fantastic, I can't think of anyone more perfect to play that part," she said of Tatum, whose Duke rewrites the Joe story line by getting romantic with Baroness. "He's a brilliant, brilliant actor and is physically big enough and strong enough. He's just the sweetest guy, just a Southern gent."

When asked about Joseph Gordon-Levitt, who plays a soldier that eventually becomes Cobra Commander, Miller said, "That character is shrouded in mystery, so I think I have to be quite discreet with that.

"We did the table reading and [Gordon-Levitt] has got this voice that he's come up with for it that's fantastic," she grinned, insisting that it's different than the hissing voice from the old cartoon. "He's gone for it, and he's done it really well."

Miller also said that all the G.I. Joe weaponry is cool — even if she isn't sure whether they're faithful to the toys that began flooding shelves in 1982.

"I'm not sure, because I didn't play with them; I was just born, man," she grinned. "It's pretty much as true as possible. We've stayed true to the original concept. I'm sure nowadays the guns would be more hard-core-looking, so I'm sure we've probably gone for the more hard-core version of guns than they had in the '80s. But I had some serious guns. They're actually models, but they fire, they have lights that flash, everything works. It was like toy heaven."

Check out everything we've got on "G.I. Joe: Rise of Cobra."

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