The first secret of my childhood was what I called my “pretty things”. It was a secret hoard of treasure. In my room was a doll’s bed, wooden and painted blue and with its own little mattress. Under that mattress was a perfect hiding place for all the small objects I would collect. My mother must have thought we had Borrowers in the house when things began to go missing - a little silver dish, a string of coloured beads, a tiny purse of soft blue leather. One day, at a friend’s house, we went through her mother’s dressing table and found the most beautiful thing ever - a slim round box of mother-of-pearl, deliciously scented by the face powder it held.

I took it home and hid it under the mattress with the rest of my hoard. From time to time I would go to my room, shut the door and take out my treasures one by one to gaze at and enjoy.

But the mother-of-pearl powder compact was a treasure too far. It was missed, and I was soon found out as the culprit. In tears I led the way to my room, the mattress was lifted and my secret hoard was laid bare. The grown ups used the word “stealing”. What I had been doing, I was told, was wicked. And I had thought I was simply collecting pretty things.

After that, I found a hollow in the stone wall of our front garden, half hidden by the privet hedge, a miniature Aladdin’s cave. In it I hid only the tiniest things - sea shells and tiny fragments of coloured glass, red, green, amber, blue. These I found lying in the roughly made roads around our house - all through my childhood the town was spreading, eating up the countryside. I still wonder about those glass jewels, how they came to be there. Sometimes I am tempted to go back and search for the hollow stone in the wall and see if my secret treasure is still there.

I had other secrets, too. The recurring nightmare of a vast underground cavern, where in the darkness a pair of green eyes glowed, the discovery that words were like music, and could sing and fall into patterns called poetry. But the greatest secret of all happened out of the blue one day in summer, when I think I was nine or 10 years old.

I was walking alone (children could, in those days) down a very long, straight suburban road. Either side were the stiff and starchy houses with their neat gardens and clipped hedges. Then it happened.

I stop, and I stand stockstill. The tar on the road is melting, I can smell it. The world about me is suddenly foreign. I think “This is not real”. I think it and I know it. Then: “I don’t belong here. What am I doing here?” I think it and I know it. It is at once terrifying and comforting. At that moment the boundaries of reality areshifted, once and forever. I have a new secret treasure and it is hidden not under a mattress, or in a hole in the wall, but within my own self.

And I spend the rest of my life writing, writing to find out the mystery that lies behind what most people call “reality”, and what I am doing here. I explore theother world I glimpsed in books like The Night-watchmen and The Bongleweed. It was the secret I discovered that hot day long ago that made me the kind of writer I am.

Helen Cresswell has written many books, some of which - The Piemakers, The Bongleweed, The Night-watchmen - have never been out of print. Her latest novel is Snatchers (Hodder). She is also a twice BAFTA nominated screenwriter and is adapting her own humorous series The Bagthorpe Saga for television.

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