Lady Gaga and Bradley Cooper have shared their duet “Shallow”, which appears in their sparkling new film, the A Star is Born remake.

The movie sees Cooper play a mature, seasoned musician called Jackson Maine, who then discovers and falls for Ally, a struggling artist just about to give up on her dreams. Jackson invigorates her, but as she begins to get noticed and ascend towards stardom, their relationship begins to break down. It’s been described by critics as a real emotional knockout, and this song is pretty much that too – an intense, pulsating ballad where they do some beautiful, twinkly harmonies and Gaga shines with some star-aligning vocals.

Gaga wrote “Shallow” with Mark Ronson, Andrew Wyatt and Anthony Rossomando, and co-produced it too. The powerful song debuted on Zane Lowe’s Beats 1 show, where the artist spoke about the film and her musical career. She talked about how Cooper visited her at her home to pitch the project, and they sang Creedence Clearwater Revival’s “Midnight Special” to test the waters.

The Joanne singer also detailed how this felt like a personal continuation of her previous, very intimate work. “I think things come in sequence and artists, you know, I think that we move to a certain cadence in a sequence in the way that we want to put things into the world that we believe in,” she told Lowe. “But especially with the song ‘Shallow’ being such a crucial moment in the film.”

“We made this song for Ally and Jack and it’s such a special song, you know. It’s two people talking to each other and talking about the need and the drive to dive in to the deep end and stay away from the shallow area.”

The A Star is Born soundtrack will be officially released via Interscope on October 5.