It seems like the "Iron Man 3" casting department has been awful busy in recent days. In addition to the casting of Ashley Hamilton as Firepower and Jon Favreau returning as Happy Hogan, it looks like there is a third actor who might be coming on board the upcoming Marvel movie.

Latino Review found out that William Sadler has been seen on the film's set recently for a costume fitting. This isn't hard and fast confirmation of his inclusion in the movie, but we can't think of anything else the "Shawshank Redemption" star would be doing in Wilmington on set except for gearing up for a role in "Iron Man 3."

Since his participation is still unofficial, it's unclear whether Sadler would play a villain or ally of Tony Stark. Our hope is for the former, since Iron Man's enemies seem to be swarming around him like flies. In addition to Firepower, there's also James Badge Dale's Coldblood, Rebecca Hall's Maya Hansen and Guy Pearce's Aldrich Killian. Oh, and we still don't know who Ben Kingsley is going to be playing.

We really don't know much about "Iron Man 3" right now other than the fact that it's mostly based on Warren Ellis's six-issue run, "Iron Man: Extremis." Hopefully we'll get some more insights into the film over the coming weeks, as it is going to be the first post-"The Avengers" Marvel film to come out and thus has some pretty big shoes to fill.

"Iron Man 3" also marks the return of Robert Downey Jr., Don Cheadle and Gwyneth Paltrow. Directed by Shane Black, the movie is set to hit theaters on May 3, 2013.

What character would you like to see Sadler play in this movie? Tell us in the comments section below or on Twitter!