"He hopes to have all other Iron Man 2 details locked down — even though he's sending dispatches via Twitter from the set. "It's never easy with summer movies, but we're trying to keep as much a surprise as possible," he says.
That means no new dirt on replacing Terrence Howard with Don Cheadle, or how the crime-fighting team S.H.I.E.L.D. will ultimately come together. Or how he'll work in new characters. Among those signed on for this go-round are Mickey Rourke as Whiplash, Scarlett Johansson as Black Widow and Sam Rockwell as Justin Hammer."