Lady Gaga convinced Bradley Cooper to sing live for “A Star Is Born.”

The pop star told the actor that a pet peeve of her’s was watching actors lip-synch to pre-recorded music in movies.

“‘What I can’t stand in movies is when it’s playback,'” Cooper said Gaga told him, before debuting a new trailer for the film at CinemaCon.

The film is an oft-told tale that has been made and remade several times over the years — with the likes of Barbra Streisand, Judy Garland, Kris Kristofferson, and James Mason essaying the lead roles. Like Streisand’s 1976 version, this “A Star Is Born” is set in the world of music. It marks Cooper’s directorial debut, and the Oscar-nominated actor said he spent three years working on the Warner Bros. production.

It’s not just Gaga hitting the high notes on screen. Cooper made a deal with Gaga. She would teach him to sing, and he would help the pop star get comfortable emoting on camera. To add to the authenticity, Cooper and Gaga performed at Coachella and at Glastonbury, where they shared the same stage as Kristofferson.

In the film, Cooper plays an alcoholic country and western singer, while Gaga is an aspiring musician who is insecure about her looks and her songwriting abilities. The trailer bills her as Lady Gaga, not as Stefani Germanotta. Initial publicity materials for the film listed Gaga by her given name.

Warner Bros. has moved back “A Star Is Born” nearly five months from May 18 to Oct. 5 because it believes the drama could factor into awards-season consideration.

Cooper came on as director following his work with Clint Eastwood on “American Sniper.” Eastwood attempted to get the film made for years with Cooper in the role of the fading movie star and Beyonce as his co-star. Eastwood eventually left the project, but not before suggesting to Cooper that he try directing.

In addition to “A Star Is Born,” Warner Bros. highlighted “Mowgli,” a new version of “Jungle Book,” “Ocean’s 8,” and “Crazy Rich Asians.”

RELATED CONTENT