"Shallow" was written by Gaga with Andrew Wyatt, Anthony Rossomando and Mark Ronson, and produced by Gaga with Benjamin Rice. The song is heard three times in the film, most prominently during a sequence when Cooper's character Jackson Maine invites Gaga's character Ally to perform it onstage with him.

For example, the melody of “Shallow” (A Star is Born) contains a low G3 and a high D5.

However, in one of his interviews, Cooper revealed that indeed it wasn't him playing in the film. Although he sang and recorded all the songs live (and did it well), the guitars were played by Lukas Nelson (the son of Willie Nelson).

'A Star Is Born' Isn't Based on a True Story, But Real-Life People Definitely Inspired It. The musical drama, also directed and co-written by Cooper, has a lot of individuality and an unforgettable soundtrack, and has become a pop culture phenomenon in the months since its release.