One morning, when I was 10, I was woken by my mum screaming “Trouble! Look out the window!” Musical artefacts were being hurled from the top-floor balcony of the flats opposite - a saxophone, a guitar, something that could have been a flute, reams of manuscript. “She caught him last night! With another woman! If Coltrane gives you any gossip - make sure you tell me!” 9(5col) = Coltrane Clay was my best friend. His dad was a jazz musician with a long history of what Mum referred to as “bits on the side”. Coltrane’s mother, the usually timid creature I knew as Aunt Rita, had thrown him out.

“Dad’s living somewhere else now,” Coltrane told me. “The Isle of Dogs. Sounds like miles away.”

It was only a short bus ride from us in Bethnal Green, east London. But the word “isle” conjured up images of faraway places, desolation, and a high probability of volcanoes.

“How exciting, Col,” I cried. “You gonna visit?” Coltrane looked horrified. “You must be joking. Mum told me all about this. Dog Island, she calls it.”

Aunt Rita hissed across the kitchen table: “He lied to me -cheated. Now he’s gone to the dogs. Ha! That’s it. Gone where all the dogs are. Dog Island. ”

Col and I decided the inhabitants must be a special breed of dog that walked on hind legs, wore clothes and spoke English. They could drive cars (although the pedals and gear stick would have to be adapted) and buy their bones and liver in the supermarket. They’d have their own TV programmes - Star Trek “Boldly going where no dog has gone before”.

And the humans on Dog Island? They’d be made to sleep on tatty blankets by the washing machine, eat left-over fish and chips on Fridays, and sent to the doctor to have their bollocks chopped off.

I drew pictures of vast concrete estates milling with every breed of dog, wearing all sorts of clothes, puppies playing on the swings, young bitches singing “Puppy Love” and “The Good, the Bad, and The Absolute Dog”. I loved thinking of Dog Island stories to wind Col up.

“I bet your dad has to shit in public. Your dad has fireworks tied to his backside. Your dad’s washed with freezing water, then left to shiver himself dry on the street.”

I scared myself more than him. I had nightmares about rabid dogs watching me defecate. Then I heard the saxophone from the flats opposite. “She’s taken him back,” sighed my Mum. “She’s a fool, but what can she do?” The saxophone played for most of the night - the sad, desolate sound of someone who had known Dog Island.

Philip Ridley’s latest children’s novel, Scribbleboy, is published by Viking Pounds 10.99 (hbk) and Puffin Pounds 3.99 (pbk). His plays and screenplays are published by Methuen (Ridley: Plays One Pounds 9.99; The Krays, Pounds 7.99; The American Dreams: Reflecting Skin and The Passion of Darkly Noon Pounds 9.99)