The ice gave way with a sound like a rifle shot, and then everything went quiet.

One moment my brother was ahead of me, laughing, his red hat bobbing across the white expanse of the frozen reservoir; the next there was a black star cracked into the world where he had been, and a hole, and nothing. The silence that rushed in afterwards was the loudest thing I have ever heard. The crows stopped. The wind stopped. Even my own scream seemed to happen somewhere far away, behind glass.

I do not remember deciding to run. I remember only the ice tilting up to meet me, the surface no longer solid but breathing, flexing under my boots like the skin of something alive. Somewhere a voice — mine, older than me — was saying lie down, spread your weight, do not stand, the words surfacing from a water-safety talk I had slept through two winters ago and apparently never lost.

I went flat. The cold came through my coat like a hundred needles, then like nothing, then like fire. I crawled, hands and knees splayed wide, towards the black star, and the ice sang and ticked beneath me, a thin high music of things about to break.

His mitten appeared at the edge of the hole — small, sodden, clawing. Then his face, blue-white, his mouth a perfect O of shock, too cold even to cry out. Our fingers missed. Missed again. The water between us was the colour of old iron and impossibly, obscenely calm, and I understood with a lurch that it would take him without malice, the way a drain takes water, simply because that is what it does.

I flung my scarf. Idiot instinct — but the wet wool slapped across his wrist and his fist closed on it with the last strength of the truly desperate, and I hauled, screaming again now, the sound back inside my own head where it belonged, until he came out of the water in one long, streaming, terrible rush and we lay together on the trembling ice, too frightened to move, breathing.

They tell you your life flashes before your eyes. It doesn’t. What flashes is one small thing you failed to say. As I lay there, cheek pressed to the ice, my brother’s heartbeat hammering against my arm, all I could think was that in the car that morning I had called him an idiot for wanting to cross the reservoir, and I had meant it, and I had been right, and none of that mattered now at all.

We crawled back the way we had come. Behind us, the ice healed over in silence.