The winter I turned eleven I came upon a certain snake in the street. This was in Londonderry, Northern Ireland, where I grew up and where no snakes should have been.

Time has blurred the context. Exactly what led me to the snake in question, how I even happened inside its neighbourhood, I can’t now imagine. All I remember is that I was walking by myself on an empty backstreet after dark and this street was dim and shuttered, curfew-silent, the way that all good Protestant streets in Derry were meant to be. It must have been a Thursday, the day we ran cross country at school, because my feet ached. Anyhow. At a given moment I turned a blind corner, and I blundered on the snake.

I didn’t register it right away. I was dazzled by bright lights and the enormity of where I was. My feet had brought me to the one place where no soul who hoped to be saved must ever venture – the downtown end of The Strand, hard by the docks, on the borders of the Bogside, the Papist war zone.