We all know about toddler tantrums and teenage moods but when Adam Long’s son refused to leave his bedroom it was much more than your usual growing pains.

Joe was diagnosed with Fragile X syndrome when he was two, a genetic condition with symptoms similar to autism that left him so anxious about meeting new people he would barely go outside.

Adam and his wife Alex had tried everything over the years to try and help their son but it wasn’t until he was 14 that they discovered the answer right outside their door in Enfield.

“He had speech therapists, occupational therapists and had gone to a special school but that hadn’t worked out. As he went into puberty his anxiety became more acute and being around people he didn’t recognise was very difficult for him,” explains Adam, who grew up in Hollywood and in the 1980s founded The Reduced Shakespeare Company with two friends as a hobby.

“We had never tried theatre before but at home whenever we played show music he would stand up and sing.”

Joe could see the famous Chickenshed building from the window of his bedroom in Oakwood and his parents. who both work in showbusiness, decided to give it a go, spending days persuading him to step outside the front door and travel the few metres to the Chase Side theatre.

“It was like magic,” says Adam in a break from co-directing new musical Miss Atomic Bomb starring Catherine Tate.

“He immediately relaxed and started taking part and this young man, who a few weeks before hadn’t been able to be around other people, was suddenly rehearsing with 100 other performers and dancing and singing.”

Joe had a part in the A Christmas Carol that year and was member of the inclusive theatre for three years, over which time Adam became involved behind the scenes, helping write and create shows.

The father-of-two is now one of 14 collaborators working on Chickenshed’s new show Sharing Stages, which aims to demonstrate the breadth of its creative partnerships with organisations such as Amnesty, Barnados, The Brits School and Young Minds and the desire to reach far beyond its walls to help create a better world.

Recalling the first time he saw a production at Chickenshed, Adam says: “It was amazing, not only to see Joe transformed on stage but to see those productions with more than 100 children on stage and every single one of them is a story of some sort. It just makes the experience a million times more potent. There is almost a spiritual function Chickenshed fulfils that commercial theatre never will.”

Audiences can expect surreal comedy, surprisingly touching moments and amazing puppetry when they watch the piece he has worked on with director Peter Dowse.

“They are very, very collaborative at Chickened and that’s one of the things I love about them. Everyone is working creatively and giving input and things take on a life of their own. That’s very exciting because it’s so different from how a lot of the theatre world works.

“I do a lot of professional theatre and that can be very prescriptive and people can be very authoritarian. At Chickenshed they value everybody’s input.”

Adam, whose London production of The Complete Works of William Shakespeare (Abridged) was nominated for an Olivier Award and ran at the Criterion Theatre for nine years, left The Reduced Shakespeare Company in 2003. He planned to quit theatre altogether to be a speech therapist but was lured back by ‘the force’.

“Lucas Film came along and asked if I was willing to condense all six Star Wars films into a half hour comedy. I love the films but didn’t want to do it so I quoted them an enormous amount of money and thought they would go away. But they didn’t and I got dragged back into showbusiness kicking and screaming and one job led to another after that.”

He has since become heavily involved with shows for children and animation, worked with Disney, Nickelodeon and Cbeebies and he is the voice of Mr Small in series two of the BAFTA and Emmy Award winning British-American television series The Amazing World of Gumball.

Joe, who has always had an affinity with animals, went on to go to college after Chickenshed and then joined a farming community in Wales. But the 22-year-old still sees shows whenever he is home.

Adam says of his son’s experience there: “It saved his life. He was housebound and the future looked bleak but Chickenshed totally transformed him.”

Sharing Stages runs at Chickenshed, Chase Side, Southgate from March 3 to 20. Details: 020 8292 9222, chickenshed.org.uk