The Knitting Circle is a new play written by Julie McNamara which paints a picture of the lives of women who lived in the old asylums of Britain's mental health system.
Set at a fictional institution in the 1980s called Harper Park, the patients face the prospect of being reintegrated into the community.
The idea came when McNamara unearthed a recording she had made 30 years ago, when she was a nursing assistant in a long-stay hospital in the home counties.
Long forgotten, the cassette contained voices of female patients she had worked with, all telling their personal stories.
"There were thousands of women in this country put away into institutions for the most spurious reasons," says McNamara. "They were written off as morally deficient, feeble-minded or imbecile."
She was there at a time when the government was closing long-stay facilities like hers, which looked after 2,000 people. The patients were institutionalised and she wanted to encourage relationships between them to help prepare for a new less-sheltered life outside.
It bothered her that the women didn't talk to each other. She says: "The only way to maintain any level of privacy when living on a 32-bed ward, was not to speak to the woman in the bed on your left or your right."
The voices on the tape were members of a group McNamara had set up to encourage patients to remember and share details of their lives before their hospital days - often a very long time ago.
A ward sister warned that a project of this nature would be considered too political and so McNamara secretly established her group in the guise of a knitting circle, but the conversations that took place within it went way beyond "knit one, purl one".
As is the way in a therapeutic environment, they had to demonstrate a positive purpose for the group. So it was decided that the results of their work would be sold by the hospital shop.
"We had to look like we were knitting for England," McNamara remembers. "There was just one problem though - I couldn't knit.
"We made nothing fit to wear, but there were some marvellous toilet roll covers, tea cosies and random contributions to the shop."
The irony was that the only people who shopped there were the patients themselves. In order to keep the circle going, they had to also prove people wanted to buy their knitted goods and so had to make it disappear off the shelves. "Those with a few pence to spare were constantly buying back their own stuff," says McNamara.
She learned a lot about the members of the circle during its eight-month lifespan, including why they had been admitted in the first place.
One woman had arrived as a baby; an unwanted child of a wealthy family who, it was thought, were trying to hide the fruits of sexual impropriety. Another knitter was admitted aged 18, having had a child outside wedlock.
"I heard stories from these women of sexual abuse and of being sent away because they were unmarried mothers," she says, "and I knew the women had things in common which, if shared, could help them make informed choices about which friends they wanted to live with when they were moved to smaller group homes."
She felt the women were anything but "feeble-minded" and were trying to live the best life they could in the circumstances.
She recalls that the women did find ways of having fun while there. One former patient, Mary, told her she stole cigarette butts from the ashtrays, rolled them up and sold them back to the staff.
Another, Ann, only recently revealed how she would get one over on the nurses each December.
She said: "I hate brazil nuts. But every Christmas, one of the nurses used to give me chocolate brazils... so I used to suck the chocolate off and give the nuts back to the other nurses. It took them four years to realize."
As the patients told McNamara: "It was the mischief that kept us going."
The Knitting Circle has a cast of eight which includes two British Sign Language speakers. They perform a script based on the recollections of 40 surviving female long-stay patients in the mental health system at the time.
McNamara wanted to build on what she had rediscovered from the tapes and, with the help of Mind mental health charity and the National Survivor User Network, gathered more stories while writing the play in 2011.
A favourite story McNamara collected came from a former patient called Hillary, who had lived in an institution in the Berkshire area. Hilary said: "I used to love it when the Broadmoor boys came by. They weren't bad boys.
"I had a boyfriend, Lenny, he was a lovely man. He used to be a road digger. And they found some bones near his patch. They were human remains ... but they weren't his."
Many of the women during McNamara's period at the hospital muddled through when discharged. For those who'd been there a long time, however, it was very difficult.
"I lived and worked alongside one woman who was put away aged nine for stealing a bicycle," says McNamara. "Forty-eight years later, they wanted to release her into the community. She was so institutionalised that it was not possible."
In preparation for The Knitting Circle, cast and crew were teamed up with surviving patients and staff. Five patients from McNamara's old hospital sat in the front row on opening night, "laughing like drains" at seeing their mischief portrayed on stage. Two staff members from the time were also there but McNamara says they remained at the back, sobbing.
McNamara believes this to be a Magdalene Laundry for the UK that isn't even in the public consciousness. The playwright, who herself has been a patient in the mental health system, hopes that her work can honour the women featured.
The Knitting Circle is currently touring English theatres, closing in Bristol's Tobacco Factory on 20 May.