By Nicole Sperling
January 14, 2009 at 12:00 PM EST

So who will be the next big-name actor to join the cast of Iron Man 2? Marvel Studios remains mum on details, but sources say Emily Blunt (The Devil Wears Prada) could play a lead character named Natasha, who goes by several aliases, including the Black Widow. Blunt is apparently one of many actresses the fillmmakers are considering, though she’s believed to be the front-runner. In other Iron Man 2 news, comeback kid Mickey Rourke is in discussions to play a villain, but he’s also negotiating a part in Sylvester Stallone’s actioner The Expendables, which is scheduled to shoot at the same time. While Rourke is hoping to be in both, scheduling conflicts may force him to make some tough decisions.