Robert Downey, Jr. has reunited with his Sherlock Holmes director Guy Ritchie to film an advert for the new Call Of Duty: Black Ops Ii video game. The action star makes a brief appearance in the minute-long live-action trailer, titled Surprise, in which he quips, "Guess who brought a jet to a gun fight", before trying to fly out of the war zone. The game hits retailers on 13 November (12).