Bradley Cooper crashes Glastonbury Festival to shoot 'A Star Is Born' scenes

The actor was shooting scenes for "A Star Is Born."

Cooper admitted on The Ellen DeGeneres Show back in May just how hard it is to portray a singer.

"It’s so hard to sing," he said then. "I had no idea. I just felt I would get fatigued at the end of even like a phrase."

"The amount of respect I have for singers, which I know is ridiculous because of course you should, but I’ve really been awakened to the phenomenon of singing," Cooper continued. "So I hope I can just be believable enough so that you can watch Stefani -- that’s her name, Gaga -- just shine 'cause she’s incredible."