Damien Chazelle wanted Justin Hurwitz to channel "loss, pain, grief [and] loneliness" in the score for 'First Man'.

Justin Hurwitz

Justin Hurwitz

The 33-year-old composer - who worked with the director on the hit 2016 musical 'La La Land' - has revealed that "themes are very important" to the filmmaker and when creating their sound for a flick, Chazelle "throws words" at Justin to find the "feel of the music".

Hurwitz admits that Chazelle, 33, was very specific about the emotions he wanted to convey in the 2018 space biopic which tells the story of Neil Armstrong, the first man to walk on the Moon and is based on the book 'First Man: The Life of Neil A. Armstrong' by James R. Hansen.

In an interview with Collider, Hurwitz said: "He's very specific in what he's looking for. So the first conversation we had once we really got into it during pre-production, we always start with ... Well, he always wants to know at the beginning what the melodies are gonna be, what the themes are gonna be.

"Themes are very important to him. It always starts with me sitting at the piano looking to the themes before we get into any instrumentation, any sound ideas. We just talk about themes and he throws words at me, words that kind of get at what he wants to feel from the music.

"For this ('First Man') he wanted ... the words he used were loss, pain, grief, loneliness. He wanted to feel all of that in the main theme of the film."

The 'Whiplash' composer went on to explain that the director "always says no" when he sends first drafts, and he simply has to "keep going" until the pair have found the right sound.

He said: "So then my job is just to sit down at the piano and look for that, try to find that, and so I feel my way around the piano until I have something that feels right to me. I record at the piano, then when I send it to him and he always says no. Sometimes he'll say why.

"It's a little too this or it's a little too that, and I'll just keep going. We do this over and over and over again. It was a few hundred attempts at it before I found the right one that was the main theme of this movie."