Near an undistinguished corner he found a clean, new feather and picked it up. It was striped pearly gray and white — dropped by a bird in haste — and he remembered how Kate had worn her clothes like plumage. He looked for a windowsill on which to set the feather, like a single lost glove, and saw a man in shabby denims smiling at him from a doorway. Breton let the feather fall, twinkling and tumbling, onto the greasy concrete and covered it with his foot.

His next action to be guided by his own identity came five weeks later, when he opened his eyes in a hospital bed.

The intervening time was not completely lost to him, but it was flawed and distorted like a scene viewed through pebbled glass. He had been drinking hard, annihilating self-awareness with raw spirit, contracting the frontiers of consciousness. And somewhere in the midst of that kaleidoscope world was born an idea which, to his fevered mind, had all the simplicity of genius.

Psychopathic killers were hard to find, the police had told him. They could not hold out much hope in a case like this. A woman who goes into the park at night alone, they seemed to be saying, what did she expect?

Breton had found himself uneasy in their presence, and decided the dismaying thing about the police mentality was that dealing so much with criminals made them aware of another system of morality. Without sympathizing with it, they nevertheless came to understand to some extent, and the needle of their moral compass was deflected. Not their direction — because so long as the amount of bias is known it is still possible to steer — but this, he deduced, was why he felt like a player who did not understand the rules of the game. This was why he was looked at with resentment when he asked what results they were getting — and at some point early in the last weeks he decided to invent new rules.

Kate’s murderer had not been seen and, as he had no circumstantial motive for the killing, there was nothing to link him physically to the crime.