"Robert Downey Jr. sustained an ankle injury on the set of Iron Man 3 in Wilmington, North Carolina while performing a stunt. There will be a short delay in the production schedule while he recuperates."
There are no specifics on what kind of ankle injury he sustained, although it does not seem to be serious. Production began in early June, with Shane Black directing from a screenplay he co-wrote with Drew Pearce.
Iron Man 3 was released May 3rd, 2013 and stars Robert Downey Jr., Gwyneth Paltrow, Don Cheadle, Guy Pearce, Rebecca Hall, Jon Favreau, Ben Kingsley, James Badge Dale. The film is directed by Shane Black.