Casey turned back to her computer again. The afternoon had worn away. Miranda glanced at her watch, and looked up, worried. ‘Tom will go spare if I’m late again.’

Miranda and Tom lived together, just, in a pretty house in Queen’s Park. In a three-wishes life that Miranda never wanted.

‘Don’t stay on too late, Casey,’ said Miranda.

She knew Casey would stay for hours.

‘I won’t,’ Casey lied. ‘You go too, Hessa.’

Hessa and Miranda left Casey there, in the glow of the investigations room, head bent over her notepad, as she raced through all the possibilities.

The start of an investigation: Casey had been here before. Within just a few years of joining the Post, she had been all over the world.

Beijing. Nairobi. Lisbon. Los Angeles.

Kandahar: just another army base. Dusty rows of tents, sprawling to the horizon. Ugly prefab blocks, fading into the sky. The quickstep of the military, at every turn. The strangeness of English snacks and American candy, out in a dusty desert. McDonald’s and Starbucks and Burger King. The Afghans, who belonged here, looking as if they were wrong here. And beyond the fence, that unknown enemy. They didn’t know, then, that he would never really fade.

Delhi. São Paulo. Madrid. Singapore.

The Promenade des Anglais: that familiar stretch of beauty, torn apart. The blue of the Mediterranean, sparkling to the horizon, and the patches of blood, black in the sun. The families, searching. That’s the worst part, really. Because the families don’t give up. Not when the phones – out beyond the police tape – stop ringing, one by one. Not when they’re told, kindly meant: there is no hope. It’s when they see the bodies. That’s when they break.

Montreal. Jakarta. Geneva. Dar es Salaam.

Minsk. Rome. Shanghai. Amman. A meat thermometer, plunged into flesh, the red digital flicker viewed coolly through heatproof glass.

Interlaced with boredom, of course. The coroner’s court in Surrey, just round the corner from Woking station, for some pointless, careless, thoughtless death.

Three days outside a redbrick house in Hertfordshire, hoping to talk to a murderer’s wife. Who didn’t want to talk to anyone, not ever again.

And the endless nights in hotel rooms, all designed to look just the same.

When Miranda had joined the Post, Casey knew at once: this.

It suited her, this job. Dissolving into roles, day after day. A flick of eyeshadow, and a touch of lipstick: then she drew the eye. Other days, she was nothing; forgettable and forgotten.

And an answer, at last, to the question: Who am I today?