There’s a good reason why there’s been so much hype around A Star Is Born: Bradley Cooper and Lady Gaga’s onscreen chemistry is off the wall.

From the trailer alone – which has been viewed nearly 11 million times – it’s clear that their relationship on the big screen is part of the reason why the film has received rave reviews.

Cooper – who directed A Star Is Born and co-wrote several songs – has revealed the surprising way in which the pair crossed paths. While attending a cancer benefit with his mum, Cooper heard Lady Gaga sing live for the first time. As a surprise, she came on stage and belted out La Vie en Rose, and Cooper was bowled over by her musical ability.

He instantly knew she was who he wanted to play the leading lady of his directorial debut.

The next day he called her agent and drove to Malibu to meet her. And they instantly hit it off.

“Surprisingly, I was not nervous or scared about the prospect of acting in A Star Is Born,” Lady Gaga told W Magazine.

“I had heard about the project through the grapevine, and I’ve wanted to be an actress since I was a child. I even took sense memory classes at Lee Strasberg [method acting school] when I was very young.

“So when Bradley came over, he immediately felt like a kindred spirit — we ate leftovers on my patio and started singing together. When I heard how soulful his voice was, I knew the movie would work.”

The film, which first hit cinemas in 1937, is the fourth version of the story to hit the big screen. The plot follows country music singer Jackson Maine (Cooper) as he falls in love with Ally (Gaga) after they cross paths in a bar.

Very much like their own story, after meeting Lady Gaga (real name Stefani Germanotta) at her home, the pair sat down at a piano to sing The Midnight Special.

“I was so happy at that moment,” Copper said, recalling the encounter. “I’m from an Italian background, and so is she. We were immediately comfortable with each other.”

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So the pair made a beautiful pact.

“We made a kind of deal: I believed in her as an actress, and she believed in me as a musician,” said Cooper. “I wanted there to be a meta aspect to the film, and Stefani gave me that.

“Also, no actress can do musically what I needed Stefani [Germanotta] to do in 42 days of shooting: I needed plutonium. And the plutonium in A Star Is Born is Stefani’s voice.”

A Star Is Born hits UK cinemas on Friday 5 October.

Images: Getty