The Oscar-nominated actor and producer concedes that the project is "a big swing," and calls co-star Lady Gaga "a revelation."

Bradley Cooper’s screenwriting, directing, and onscreen singing debut has already earned raves from four-time co-star Robert De Niro. At CinemaCon on April 24, the first trailer for “A Star Is Born” had the National Association of Theatre Owners and their guests not only smitten, but also sensing an award-season contender. Warner Bros. Motion Picture Group chairman Toby Emmerich called Cooper’s three-year endeavor about musicians who pair up and reverse fortunes “extraordinary.”

Damn, A Star is Born looks powerful, I cannot lie. #CinemaCon — Kevin Polowy (@djkevlar) April 25, 2018

First trailer for A Star Is Born gave me chills. Lady Gaga’s Hollywood moment is far from over. Music is phenomenal. #CinemaCon — Crystal Bell (@crystalbell) April 25, 2018

Bradley Cooper introduced the first trailer for A Star Is Born. It’s obviously a passion project for him and that earnestness shows in the footage. Lady Gaga was really impressive even in a couple minutes of footage. Very natural, real, vulnerable. This one might be something. — Eric Vespe (@EricVespe) April 25, 2018

Was very very skeptical but … The A Star Is Born trailer is 💥💥💥 #CinemaCon — Ryan Pearson (@ryanwrd) April 25, 2018

I mean, the trailer for “A Star is Born” just made me cry. Signed, sealed, delivered, I’m yours. #CinemaCon — Amy Kaufman (@AmyKinLA) April 25, 2018

Was very very skeptical but … The A Star Is Born trailer is 💥💥💥 #CinemaCon — Ryan Pearson (@ryanwrd) April 25, 2018

“It’s a big swing, this movie, I totally get that,” said Cooper, a four-time Oscar nominee as either an actor or producer. “But you can’t control what moves you. You can’t really contrive or manufacture something that moves you, and I’ve always wanted to tell a love story, and this project was around before and it always stayed with me. And to me, music is the most purest way that you can communicate love, because you have to be relaxed.”

Making her film debut, Stefani “Lady Gaga” Germanotta” (Golden Globe winner for “American Horror Story: Hotel”) plays Ally, a performer discovered by famed country crooner Jackson Maine (Cooper) when he catches her rolling onstage — in drawn-on eyebrows — during a club set.

“Almost every person told me they liked they way I sound, they don’t like the way I look,” the brunette tells Jackson when she’s back in her casual clothes, a huge departure from the Gaga persona, once known for meat dresses and hatching from an egg at the Grammys.

Warner Bros.

Later, Maine drags her onstage for an impromptu duet; they sung live during concert scenes, shot before thousands of festival-goers at Coachella, Glastonbury, and Stagecoach. As Maine falls in love and introduces Ally to the luxuries of private planes and tour buses, he descends deeper into alcoholism, shattering their relationship. Watching it all is his oldest friend, a blues musician named Noodles (Dave Chappelle). Andrew Dice Clay and Sam Elliott also have supporting roles.

The three previous iterations of “A Star Is Born” were each nominated for Academy Awards, creating onscreen couples from Janet Gaynor and Fredric March (1937), Judy Garland and James Mason, and Barbra Streisand and Kris Kristofferson (1976). Kristofferson even loaned Cooper some of his Glastonbury stage time in 2017.

“A Star Is Born” arrives in theaters on October 5 via Warner Bros.

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