Bradley Cooper put together a very specific set of mannerisms for his character Jackson Maine in A Star is Born.

Hunched over, he rarely looked other characters in the eyes and mumbled in a booze-addled drawl.

In order to keep this consistent, he chose to stay in character while in his director role, even in his most inebriated scenes. “Especially the Grammy scene,” he told Vanity Fair, referring to the one where (spoiler alert) Jackson is so drunk he wanders on stage and wets himself.

“Thank God the actors were willing to allow me to direct them sort of in that state because it was easier to stay in that space,” Cooper said. “It just took me a little longer to communicate what I wanted.”

Cooper’s character battles alcoholism for the majority of the movie (Warner Bros)

His cast were happy to go along with a slightly unintelligible director, Lady Gaga saying: “It was like a magic trick for us... really, he was like Houdini.”

One of the film’s most moving moments comes when Jackson finally opens up to his brother, played by Sam Elliott, appearing to force the words out quickly lest he start crying.

Elliott was stunned by how Cooper juggled acting this scene with directing it.

“To see Bradley get out, perform that beat, shut the door” [and then immediately shift into director mode] “and pick up a monitor, walk around to the front of the truck . . . I’m there like, ‘What the f**k, man? I’m still in the scene,’” he told Vanity Fair. “It was a really incredible moment for me to see Bradley-actor [switch into] Bradley-director. We did two takes of that.”