Unable to play video. While some fans might imagine the filming of Avengers: Infinity War to be a months-long, star-studded affair, the production probably didn't play out the way they thought. Speaking with RadioTimes, actor Benedict Cumberbatch revealed that one of the movie's main stars Josh Brolin was not present for a lot of filming, replaced by a stand-in who did a lot of the motion capture work. It's often the case you can act with other actors anyways, in certain scenarios because of the amount of additional stuff you have to fit in with the environment or the magic or whatever it is that's coming out of your hands or your ass." Either way, Cumberbatch isn't sweating the lack of Brolin on set.