Jon Favreau is already thinking about a third Iron Man movie.
The actor turned filmmaker is back in the director's chair with Iron Man 2, which sees Robert Downey Jr return to the role of Tony Stark.
In an interview with Comingsoon.net Favreau said: "I think you gotta introduce Mandarin in the next film. Fortunately, what's happening now is that we kept our films very tech-based in 1 and 2.
"We exaggerated technology, but beyond that, it's kind of a real set of circumstances. The politics and everything reflects reality.
"When I read Marvel comic books, I lived in Queens and they were fighting in Queens and it was in New York. That is what made Marvel different, so I really liked the idea of using a real backdrop.
"Well, now as you start adding elements from the books that people have come to accept in reading comics and you're asking them to accept those things in the movies, "Thor" is going to have the challenge of introducing magic and the supernatural, so as that starts to expand on the rules of the universe that we established, that might open the door for a magical Mandarin type character.
"I don't know what's happening yet. I don't know what "Thor" is going to do and what "Captain America" is going to do and "Avengers" is going to do.
Iron Man 2 looks set to be one of the biggest movies of the summer and comes two years after the unexpected success of it's predecessor.
But before a third movie Favreau is working on Cowboys & Aliens, filming expected to get underway later this year.