The sound the harbour makes at the hour nobody is awake for

I had a scene that would not sit still, so at three in the morning I did the thing I always tell other people not to do, and went outside to look at the real version of the place I was failing to describe.

The harbour at three is not quiet. That is the first thing nobody tells you. It is full of small, busy sounds that the daytime drowns: the hollow knock of a hull against a tyre fender, a halyard ticking against a mast like a clock that has lost confidence in the hour, water working away at the underside of the jetty with the patience of something that has all the time in the world and intends to use it. I stood at the rail with my hands going cold and listened to a place I thought I knew do its night shift.

A cat crossed the slipway, stopped, decided I was furniture, and went on. Somewhere out past the breakwater a single light moved, too slow for a car and too low for a plane, and I never did work out what it was, which was the best thing that happened to me all night. A writer of my sort lives on exactly that: the light you cannot name, moving at the edge of what you can see.

I had come down to settle an argument. My chapter wanted the harbour to be sinister and I kept writing it sinister, piling on the fog and the creak and the long shadow, and it kept reading like a person trying too hard to frighten you, which is the one thing that never frightens anyone. Standing there I understood why. The place was not sinister at all. It was indifferent. It was simply getting on with its night and had not noticed me arrive and would not notice me leave, and that is far colder than any shadow I had been inventing. The fear was not in the dark. The fear was in being, for once, completely beside the point.

So I went home and took all the fog out. I let the harbour be ordinary, busy, uninterested, and I put my character at the rail with cold hands, listening, waiting to matter to a place that had no plans to notice her. It worked the first time. It always works the first time once you stop lying about where the dread lives.

People ask me what really happened on the crossing, in the book, and I only smile, because the honest answer is dull. Nothing happened, for a long time, in a place that did not care, and that was the whole of the horror. I learned it at three in the morning from a halyard and a cat and a light I could not name, and I have never once thanked them, so I am thanking them now.

A harbour at an hour nobody keeps is where The Tide Clock begins: a clock above the harbourmaster's office, stopped for forty seven years at twenty past four, and a town that never discusses why in front of strangers.