Known prankster [1] George Clooney [2] brought his A game to the Berlin Film Festival photocall for Hail, Caesar! [3] on Thursday, where he had the entire cast in stitches. George had a little help from tap-dancer extraordinaire [4] Channing Tatum [5] to get an unsuspecting Josh Brolin [6] laughing so hard he was nearly on the floor, and even the regal Tilda Swinton couldn't help but crack a smile. Keep reading to see more photos of the cast goofing off, and check out what happened when George and Rihanna played a game of "Never Have I Ever." [7]