The origin story of the film's original song, Come Back and Love Me Tomorrow, is another example of one of those fabulous moments of serendipity that the production of Provenance seems to have been blessed with.

In one of the film's most emotional moments Sophia dances along to a record that has great personal significance to her. We spent a long time trying to find the perfect song and were drawing a blank - the ones we liked were too expensive and the ones we could afford weren't quite right.

Amanda Atkins, the film's producer, was looking to rent somewhere in Entrecasteaux where she could stay during the shoot and that had a large enough kitchen to allow her to cater for the crew. One of the people she got in touch with, via Airbnb, was Paul Handley.

Paul was interested in why Amanda was looking for a place to rent and, when she told him that she was producing a film, Paul mentioned that he was a musician and composer.

The possibility of the song being an original, written specially for the film, had crossed our minds and Amanda thought it would be a good idea to ask Paul if he would be interested in trying to come up with something. We gave him a brief, told him the sort of songs we liked and sent him a copy of the script.

Below, Paul picks up the story of what happened next.

The full script arrived with me the morning before I set off for my 2016 Easter break to my house in Entrecasteaux - which was quite timely as I could take inspiration from the location when thinking about the music.

The song itself had to be timeless and I decided it should sound like an old classic - something that Ella Fitzgerald, Sarah Vaughan or Etta James, one of my favourite artists, might be comfortable performing.

I knew the importance of the song to the lead character and so knew that it needed to have great emotional resonance and impact. I thought it was important that the lyrics, whilst not giving anything away, could also complement the themes and plot of the film.

With all of these thoughts running around my head, and after reading through the script twice, I sat down at my piano in France and wrote a lovely verse for one song which I felt was the 'one'. The lyrics reflected the emotions one feels after separating from a lover and also tried to capture the descriptions of feelings like touch, or breath, and how that affects and controls one's heart.

A week after my return to London, I was in MAP Studios in Kentish Town where, suffering from a bad virus and sounding a little like Tom Waits, I managed to thrash out rough versions of the track.

Once the other instruments had been recorded for the demo, and sticking to my original idea that a female vocalist was required, my partner, jazz singer Louiza Friday, re-recorded the vocal line.

I submitted the song to Ben and Amanda for consideration and I was delighted when they chose this one.

After the song had been chosen, and in keeping with Amanda's desire to give opportunities to fresh new talent, Paul put out a call to music schools in London to find our singer.

After screening fifty-eight singers from music colleges, Paul short listed and 'live' auditioned twelve singers and then submitted recordings of four to Amanda and Ben. Everyone was unanimous in the choice of Maia and so the final recording plans were made.

I had already decided we needed a classic sound and made the decision to record the song 'studio live' to get that authentic ambient tone. We returned to MAP Studios in Kentish Town and recorded the rhythm section in the live venue there.

Maia and I, together with drummer Iain McFarlane and bassist Ray 'Lord Bass' Wright, had been rehearsing the song over the preceding weeks and now performed the song live, over and over, until we were happy.

I had just finished work on Renaissance, my own new studio in North London, and I was very proud to make the song our first professional recording project.

I began the first session and decided to re-record the keyboards before laying down the strings and brass section. It was during this session that we recorded the lovely tenor sax solo played by sax player Michael Powell.

As the song started to take shape, I thought that the brass section lacked depth and so decided to write and play a trombone part myself.

With all the instruments recorded and the song fully arranged, we made the decision to re-record the vocals as a clearer idea of the vocal style had become apparent. Maia came back to the studio to record the final vocals and the song was complete.

The final stage in the production took place at Renaissance as we mixed the track. When I was happy with the work, I submitted it to a top industry mastering guru, Barry Grint at Alchemy Mastering.

I was thrilled to receive an email from Barry that said, 'Next time you record a song, could you leave me some work to do!'

I was delighted to be involved in this project and was only too happy to help Ben and Helen when they needed to re-record some of the classical elements - again at Renaissance. Ben is a very generous collaborator and receptive to all ideas. We had a great time working together.

When I went to the Cast & Crew screening in November 2016, I realised that I hadn't seen the film before as an entire piece. I remember being the most nervous I had ever been before in my career as I sat in the dark and listened intently to the film. It's a fantastic piece of work and I have been delighted at the reception to "Come Back and Love Me Tomorrow."

John (Christian McKay) and Sophia (Charlotte Vega) in a still from Provenance © White Horse Films Ltd, 2017.