"HOW does a man get on a plane at Manchester Airport and end up going to Skiathos with just £30 in his pocket, a pair of shorts, a T-shirt and some flip flops?" Actor Mark Lockyer is attempting to recall a few episodes from his life in the mid-90s - a period when through a combination of bipolar disorder, drink and drugs, he went from being one of the country's most promising young actors to being homeless, penniless and eventually in prison.

"When I became unwell I did what a lot of people who are stressed do and I drank more," he continues. "For a short time it relieves the symptoms but I didn't even know I had a mental health problem, and I also didn't know that drinking or taking drugs is like pouring petrol on that fire.

"The edit button didn't exist and I'd end up with all these weird and wacky people and in some extraordinary situations which I'd never dream of getting into as a well man. When I look back on it some of it was utterly hilarious.

"It's a great story too and believe it or not it's very funny. I retell the most appalling things that happened with a great big grin on my face because some of it was hilarious. The situations I got myself into..."

Written and performed by Mark, Living With The Lights On is the actor's searing account of his manic depressive breakdown which descended on him when he was playing Mercutio in the RSC's production of Romeo and Juliet in Stratford Upon Avon in 1995.

The illness saw him walk out on his stage career and embark on a disastrous and terrifying journey that ended up in Belmarsh Prison and the secure unit in a psychiatric wing of hospital. What emerges is an extraordinary piece of theatre, a terrifying and captivating story and a spellbinding performance from Mark, who is now fully recovered and has returned to a successful acting career.

"Coming to Theatr Clwyd will be my 83rd, 84th and 85th time I've performed Living With The Lights On," explains Mark. "It's very tiring physically to perform - I'm acting non-stop for an hour and 15 minutes, playing all the characters and driving the narration.

"When you're on stage with other people you can share the load and someone else can take the baton but the way that I do it, there is a lot of fast changing and it never quite stops. It's like running a 200m race on stage."

Mark recalls how one sunny afternoon he had nothing to do and decided to get out of town and go for a walk along the bank of the river Avon. An encounter along the way changed things profoundly and forever and from that point, he started to lose control of his life.

"It was terrifying," he admits. "I was a young actor, doing really well and then very slowly my behaviour started to disintegrate and become very negative. I felt like I was possessed by something and it was very disturbing to feel so powerless about something that at that time was undiagnosable."

Mark is pleased that attitudes towards mental health have improved and believes his recovery is testament to the fact that mental illness can happen to anyone, that the bipolar mind is not a deficient one and that, with the right treatment there can be a life beyond it.

"Whether you work in a bank, a hospital or a travel agents there are now safeguards in place as there are in the theatre and drama schools, for people in emotional distress," he says. "When I was unwell in 1995 there was no such thing and people were very afraid and perplexed about what to do, which was part of the problem.

"I would never have gone down to the depths I did if there had been safeguards in my workplace and I feel very strongly that people should be looked after by their employers. My employers would just give me a bigger part or more responsibility, which led to disaster.

"I'm not really doing the show about me - it's actually about everyone else because so many people now will come forward and admit that either they've experienced mental health problems or a family member or a friend has. It is so endemic in our society these days that we need to start talking about and stop it being a stigma. There's no shame in it because we all struggle with our feelings."

Last year Mark returned to Stratford to receive rave reviews for his portrayal of the eponymous alchemist in Polly Findlay's production of Moliere's play at the RSC and he reiterates the fact that he is now well and working should give hope to anyone.

"I saw a lot of sadness in other people and saw people who would probably never get better and I didn't want to be like that," he adds. "Once I turned the corner I had to make a fundamental decision - did I want to live or did I want to die? It was as basic as that and I wanted to live. Once I made that decision, things got better."

Living with the Lights On, written and performed by Mark Lockyer, is at the Emlyn Williams Theatre, Theatr Clwyd, from Wednesday April 10-12. For more details or to book tickets, visit www.theatrclwyd.com or call 01352 701521.