Thanos may have succeeded in wiping out half of the entire universe at the end of Avengers: Infinity War, but the actor who played him, Josh Brolin, had no idea about the tragic event until he actually saw the movie. Despite filming both Infinity War and Avengers 4 back-to-back, many of the Marvel stars didn't see the full scripts for either movie. No one told him that his action would cause the deaths of several major characters, including Black Panther and Spider-Man. It wasn't until the world premiere of the film in April when Brolin, along with co-star Chris Hemsworth, finally saw how the movie ended, and neither one were prepared for the outcome.