Bradley Cooper stopped by The Ellen Degeneres Show this week, where he discussed the runaway success of A Star Is Born, and the reaction to his and Lady Gaga's now legendary Oscars performance. But he also revealed some fun secrets about filming scenes for the movie, in particular his character Jackson's live performances. As well as filming at Stagecoach in the USA, Cooper and his band also took to the stage in front of tens of thousands of music fans at Glastonbury. In a serendipitous turn of events, they were there at the invitation of Kris Kristofferson, who was in the 1976 version of A Star Is Born. But if fans were expecting a surprise opening act they were quickly disappointed, as Cooper revealed that there was actually no music! Since the songs from the movie couldn't be shared at that time the PA system wasn't used, and they essentially played a silent gig in front of 80,000 people. "I actually built in, if people threw bottles at me and were screaming, that his descent would happen very fast in the movie," Cooper joked to Ellen, as she and her audience tried to come to terms with the fact Cooper played a festival . . . without really playing a festival. Hear him tell the story for himself in the video, plus hear about his plans for more A Star Is Born performances in the future.