March 1970. Exhausted from touring, and struggling with new studio technologies forced upon them by an expectant record company, Pink Floyd labour under the pressure of following up their first top five album.

With their ambitious yet poorly defined instrumental first side in need of some serious inspiration, the band turn (with more hope than expectation) to Ron Geesin – an unknown Scottish composer, multi-instrumentalist, and sometime golfing buddy of Roger Waters.

Hoping Ron would add a new dimension, the band gratefully hand the 27 year old the tapes of their Abbey Road sessions before quickly shipping off to tour the US; leaving Ron with only vague instructions to write something ‘orchestral’…

Over forty years later, Geesin’s role in the inspired, and often fraught, making of the Floyd’s first UK number one album, Atom Heart Mother, is the stuff of rock and roll folklore.

Yet Geesin himself would tell you his involvement in the making of Mother – one of the seventies first, flawed musical gems – is indicative of most of his career. It was just a case of taking his chance well.

So whether it was contributing to the soundtrack of an Oscar nominated movie, forays into record producing, or touring with the likes of Genesis and The Who, Geesin’s career has always been more about grabbing these random opportunities than following some greater, grander plan.

From falling in (and then running away to London) with his first proper band, to having his music taught on the French school curriculum, Ron Geesin: An Improvised Life charts his multi-layered and labyrinthine career as musician, composer, performer, humourist, writer, and collector.

And let’s not forget – some would also add troublemaker to that list. What did he do, indeed, to force Genesis to cancel the opening night of their 1973 UK tour? And why to this day, does The Who guitarist, Pete Townshend, still compare Geesin to ‘a terrorist’?

With contributions from David Gilmour, Peter Gabriel, Pete Townshend, Robert Wyatt (Soft Machine), Bridget St John, and Michael Dempsey (The Cure) to name but six, the film documents Geesin’s musical life – from the London-bound seventeen year old jazz pianist, to the present day, now 71 and having recently staged his last major live performance.

An Improvised Life details how Geesin came to be involved with Atom Heart Mother, its sometimes fractious writing and recording process, and its 2008 revival (including never before seen footage of Gilmour at that magical London performance).

The film charts the adoption of the piece by the French Baccalaureate and a subsequent major performance in Paris. Interviews with Gilmour and Nick Mason, and clips from the Paris performance augment Ron’s memories of the venture, whilst contributions from Townshend, Gabriel, Wyatt and St John richly illustrate Geesin’s time in the seventies as record producer and support act.

Of course, Geesin also wrote soundtracks for several feature films – Sunday Bloody Sunday, Ghost Story, The Girl in the Picture, and numerous TV programmes and adverts – and directors Murray Grigor, Anthony Penrose and Stephen Weeks share their insights on his work. The film also features his hilarious contribution to the anarchic Channel 4 Hogmanay show Scotch Myths.

Along the way we learn of Geesin’s other loves – his encyclopaedic knowledge of early jazz, his restoration of rare 78 records, and a recent installation work featuring his composition based on recordings of blackbird song.

Throughout, the film is infused with Ron’s humour, extraordinary talent and his unique take on the world.

He is, after all, just making it up as he goes along.