Sentenced to 12 months in Wormwood Scrubs for assault during the Brixton uprising of April 1981, the 18-year-old clenched his eyes shut as the reality of prison confronted him.

He opened them to find a Rastafarian cellmate two decades his senior offering him a cup of tea. Alex snubbed the overture.

“I wanted to be left to writhe in my own self pity,” he admits today. But his cellmate, Simeon, had other ideas. After several days of tension, Alex – who had grown up in care after being born in London to Jamaican parents – poured out his heart to the older man.

“I’d had a very traumatic young life.

Living in fear in a children’s home was my normal,” recalls Alex, now 59. “But even though I had lots of trauma, I was a very competent reader. It was my secret weapon.”

It was then that Simeon handed him a book about black history and encouraged him to read. Having been brought up in a mainly white children’s home, Alex knew little about his heritage. The encounter – and the sense of identity that followed – was to change Alex’s life.

Today, he is an award-winning author and playwright, his books for young adults have inspired generations and he is proud to support the Daily Express Christmas campaign for Give A Book.

“My own experience is an example of how reading can change lives. Reading is a great leveller, especially in this cost-of-living crisis,” he insists. “Anyone can go to a library and raise their expectations. Everyone can build empathy into their lives just through reading. Simeon was a well-educated man whose hunger for knowledge had led him to black US literature.”

Hooked on comics, Alex didn’t have much access to books until he was hospitalised for chronic asthma aged eight and was lent a copy of Treasure Island by Robert Louis Stevenson. “I discovered a place I could escape to in my mind,” he recalls. “It was the first novel I’d ever read and, from then on, each time I read a book, and cape s. hen it gave me an escape from my harsh existence,” he recalls today.

Growing up in the notorious Shirley Oaks Children’s Home in Croydon, south London, reading had proved an emotional and intellectual sanctuary from the deprivations and abuse that underscored his daily life.

“Simeon encouraged me to rediscover my love of reading,” he says. “He told me I had so much more to read to discover my own history. Growing up, I was hungry to read about my own experiences but my life was absent. I remember enjoying Kes, Oliver Twist, Little Dorrit and Martin Chuzzlewit, but where was the young black kid living in a home in Brixton, and struggling to find his identity? It didn’t exist, so I decided to create it myself.”

His first novel, Brixton Rock, took five years to write and received 30 rejections before finding a publisher. It won the London Arts Board New Writers Award and was later adapted for the stage.

Alex has now written a stack of titles for teenage readers. In 2008, he was made an MBE for services to literature, having become a passionate spokesperson for the difference that reading can make to a life.

Now he goes into prisons and schools to inspire others – which is how he came across Give A Book, the Express’s Christmas charity partner, whose aim is to promote reading in the hardest to reach places.

“There was a reading group at Wormwood Scrubs and it really enthused me. These guys were trying to prepare for life on the outside.” As for his former mentor, Simeon devoted his final years to introducing more young people to literature until his death seven years ago.

“He was a champion of reading in primary schools,” says Alex. “I’m still grateful for the opportunities that presented themselves to me while I was in prison.

“Meeting Simeon accelerated a process that has enabled me to realise my creative potential and having him as my mentor helped me become the man I wanted to be.

“Reading books can inspire you, and they can also help you discover how to make a worthwhile contribution to society.”