‘You have been warned, I’m going to be contrary,’ sings the beautiful Catherine Ireton on God Help the Girl – the new album written by Stuart Murdoch of Belle and Sebastian fame. Murdoch could be speaking about himself, for he has always confounded creative expectation.

God Help the Girl feels like a natural extension of the Murdoch formula (or anti-formula) that provided B&S with such passionate fans. In GHTG (as it was with B&S) story is key – both the intrigue and melodic story of the songs, and the wider story of how the music is made, as Murdoch wants it to be, without having to play the music industry games and tick corporate boxes.

GHTG was born when Murdoch started hearing and composing songs for female voices. Having once trawled Glasgow cafés for B&S members, this time he held internet auditions to find vocalists for his ‘60s girl group’ album. He placed an advert in The List: ‘Girl singer needed for autumnal recording project. Must have a way with a tune. Celine Dion wannabes save your breath. Ballpark, Ronettes, Friend and Lover, Twinkle.’

As fate would have it, the resulting lead vocalist, Catherine Ireton, was not an applicant per se, but a friend-of-a-friend. Murdoch’s wife, Marisa Privitera, tricked him into listening to Ireton sing.

Her exquisite voice leads us through an emotional narrative, depicting the main character of Eve, a young girl trying to rebuild her life in Glasgow after a spell of chronic illness in hospital. Eve hooks up with James and Cassie, two further characters that grew out of the songs.

The musicianship is layered and lush, and the production is crisp as apple from the fridge. Thus far, more than 80 musicians have taken part, including a 45-piece orchestra directed by Rick Wentworth (Withnail and I). There is a tapestry of different tones and tempos and echoes of classic Abba and Queen. Murdoch has a wonderful capacity to catch the heart off guard with the simplicity and honesty of his lyrics. In hospital with anorexia, Eve (Ireton) sings: ‘I read a book a day like an apple, but I did not eat. And so the doctor came to me. He said a woman does not live by the printed word, forgive yourself and eat.’

Murdoch has now taken the project a leap further by writing a film script around the characters he discovered through song. God Help the Girl (the musical) has a key ally in Hollywood Producer, Barry Mendel (Rushmore, The Life Aquatic with Steve Zissou) who is helping with development. Mendel can clearly see Glasgow as the setting for this indie musical hybrid.

‘I’m sure the film would be a perfect expansion of Stuart’s creative ambition and a very singular piece of work. Stuart was also a great tour guide for Glasgow. He took me to these little dancehalls and cafés and I really saw the film come alive in my head.’

Mendel hopes that Murdoch will direct the film and he’s willing to invest his professional trust.

‘One of the great things about this project is that Stuart had the experience with Tigermilk of having no clue what he was doing, and he had the faith that he could figure it out. It’s fundamental to GHTG that he figures out how he wants to go about it. I don’t want to deprive him of that and sometimes I have to bite my tongue. But if he was about to hit an iceberg, I’d say, “Hey, there’s an iceberg.”’

With an iceberg-free horizon ahead, lead singer Ireton shares her excitement and enthusiasm. ‘In the beginning, Stuart urged me not to get my hopes too high. There was a long period of waiting-to-hear and my family started asking, who is this guy? And now it’s incredible to have this finished album.

Fellow vocalist, Celia Anne Garcia described the buzz of recording. ‘Before we sang, Stuart described the locations, the action, the mood and what the characters were thinking.’

Plans are afoot for a handful of select promo gigs in June. And if the film gets made, would the singers double up as actors? ‘Ideally,’ is all Murdoch will allow, before disappearing to work on the script. He has agreed to international interviews, but wanted the girls themselves to chat to the UK press. Acting in the film is something that Ireton would love and her background in theatre can only help. ‘Stuart writes so easily and so well. I can relate to the isolation of Eve and I could see this being a new type of musical that never patronises an audience. The characters are so accessible and – well, so normal.’

It’s a new type of musical for Scotland, certainly, but it wouldn’t be the first time that a record has become a stage play and/or a musical film. Jesus Christ Superstar, Evita and Quadrophenia were all albums-to-films. In hope and anticipation of a similar leap, Murdoch’s wife, Marisa Privitera has been making a documentary about the GHTG project from its conception. The Guardian will feature five exclusive episodes from Privitera’s film on its website. Privitera intends her final film to be a feature-length popumentary to submit to the film festival circuit.

Surely she will be partisan about her subject? She laughs. ‘Yes, of course I’m rooting for the project, but I can’t control the outcome and I’ll keep filming whatever it may be. I think people who see the film will also root for everyone involved. Whatever happens, it’s been great capturing the process from the grassroots up.’

Producer, Barry Mendel agrees that the film needs time to grow from the album. ‘It’s the only way that anything good ever happens. Nothing good can be forced. Good writing tends to come from within, not without. One has to be patient with that.’

So, every few years, the Scottish film industry comes up with a belter of a film (Gregory’s Girl, Local Hero or Trainspotting) that succeeds internationally, while remaining true to the idiosyncrasies of Scottish life we all recognise and celebrate. We see ourselves portrayed with affection on a world stage and we’re thrilled by it. Could GHTG have the ingredients to transport us to those heady heights? ‘Well, I don’t want to jinx it,’ says Murdoch, with classic Scots canniness.

If the film takes off, any appreciation of success won’t be lost on Murdoch. He is open about the fact that his songs and script are partly autobiographical. His young characters are caught between teenage and adult worlds, struggling to find comfort, wading through illness and experimentation (‘buying hallucinogens from a pair of hooligans’). Murdoch himself spent many years laid low with Chronic Fatigue Syndrome. Writing songs was the beginning of his recovery and a turning point in his life. On ‘Perfection as a Hipster’, guest vocalist, Neil Hannon (The Divine Comedy) sings about the irony of missing your moment. ‘My dream was realised and I was sleeping.’

Not this time, surely.

God Help the Girl is released on Matador records on Mon 23 Jun.

More imaginary soundtracks

Brian Eno

Music for Films (EG 1978)
The original electronica egghead created three volumes of sonic trickery that helped define the notion of ‘ambient’ music for many with these textured, otherworldly soundscapes. Oddly enough, he never actually wrote music for a film until the tunes he and U2 produced as Passengers when they recorded songs for Heat, Ghost in the Shell, Miss Sarajevo and Beyond the Clouds.

Paul Haig

Cinematique (LTM 1991)
The reclusive one-time Josef K man has issued three albums of ‘themes to unknown films’, harnessing his love of luscious synth pop and classic swing in his own sweet, if eccentric style.

David Holmes

This Film’s Crap, Let’s Slash the Seats! (Go! Discs 1995)
With Holmes’ first album as an artist, the Belfast-born DJ indulged his love of all things cinematic in his own uncompromising way, from the brooding Craig Armstrong-alike strings down to the punkish title. Something of a calling card, the album’s retro funk and widescreen electronics paved the way for him doing real soundtracks, including Steven Soderbergh’s Out of Sight and Ocean’s 11.

Barry Adamson

Moss Side Story (Mute 1998)
The record that brought Adamson into his own as a solo artist after spells with Magazine, Visage and Nick Cave’s Bad Seeds is a breathtaking imagined film noir set on the grimy Manchester streets he grew up in, replete with breathless dialogue, Lalo Shifrin and Leornard Bernstein-inspired shrills and growls. Despite having recorded several other imagined soundtracks this remains the definitive Adamson album.

Nine Inch Nails

Year Zero (Interscope 2007)
Trust Trent Reznor to render his own apocalyptic vision of the future in musical form for us. There was talk of Year Zero’s bleak, Big Brother-ish dystopia being made into a TV series and, while Reznor said last year the project was ‘still churning along’, it appears to be languishing in development hell.