I’ ll never forget the night it snowed over Calcutta. The calendar at St Patrick’s Orphanage was inching towards the final days of May 1932, leaving behind one of the hottest months ever recorded in the city of palaces.

With each passing day we felt sadder and more fearful of the approaching summer, when we would all turn sixteen, for this would mean our separation and the end of the Chowbar Society, the secret club of seven members that had been our refuge during our years at the orphanage. We had grown up there with no other family than ourselves, with no other memories than the stories we told in the small hours round an open fire in the courtyard of an abandoned mansion – a large rambling ruin which stood on the corner of Cotton Street and Brabourne Road and which we’d christened the Midnight Palace. At the time, I didn’t know I would never again see the streets of my childhood, the city whose spell has haunted me to this day.

I have never returned to Calcutta, but I have always been true to the promise we all made to ourselves on the banks of the Hooghly River: the promise never to forget what we had witnessed. Time has taught me to treasure the memory of those days and to preserve the letters I received from the accursed city, for they keep the flame of my memories alive. It was through those letters that I found out our palace had been demolished and an office building erected over its ashes, and that Mr Thomas Carter, the head of St Patrick’s, had passed away after spending the last years of his life in darkness, following the fire that closed his eyes for ever.

As the years went by, I heard about the gradual disappearance of all the sites that had formed the backdrop to our lives. The fury of a city that seemed to be devouring itself and the deceptive passage of time eventually erased all trace of the Chowbar Society and its members; at which point, I began to fear that this story might be lost for ever for want of a narrator.