Speaking in a BBC Scotland documentary, the former schoolgirl campaigners said has serious doubts when director Cora Bisset had told them she was planning to turn a child detention into an all-singing and dancing spectacle.
But they tell the programme how they burst into tears when they walked into a rehearsal of a show they now describe as “a love letter to Glasgow.”
The Glasgow Girls musical was initially staged in 2012 at the Citizens Theatre before transferring to the Theatre Royal Stratford East in London. It is currently on its most extensive tour yet after becoming the biggest selling show at this summer’s Edinburgh Festival Fringe.
Bissett tells the BBC Scotland documentary: “It was a story led by a group of teenage girls who just have a passion for life, a kind of defiance and a fearlessness. I just felt it deserved a bigger, bolder and more popular form. I thought a musical was the best way to do that.”
Amal Azzudin, one of the seven Glasgow Girls campaigners, who famously tackled then First Minister Jack McConnell over the treatment of asylum seekers in the city, said: “I just looked at her (Bissett) and thought: ‘what?’
“I was like: ‘Do you know what our story it is about? It’s about child detention. How are you going to make a musical out of that?”
Another campaigner, Emma Clifford said: “I must have burst out laughing. How on earth she was going to turn a story about seven wee lassies from Drumchapel campaigning for the rights of child refugees I didn’t know.
“But she did a wonderful job and the way it turned out is kind of like a love letter to Glasgow.”
Bissett said: “Teenagers get a very bad press. I think we underestimate their skill and bravery. Here was a bunch of girls who wanted to be lawyers and activitsts. They wanted to go out, literally grab the world and make it better.
“I’d been developing close relationships with the girls and had absolutely vowed that I would involve them at every stage.
“At the end of a long week where I’d been working with all the actresses the girls walked into the room. At that point the actresses were right in the middle of singing a five-part harmony of what was to be the anthem of the Glasgow Girls.
“I think they were quite blown away by it.”
Azzudin said: “We all started crying and they cried. Nobody knew why everybody was crying but it was a great feeling.”