Lockhart thinks of Goodison’s face, the friendliness in his eyes, and he thinks, how could you make an offhand remark about a suicide on a railway station if your own girlfriend had died that way less than two years previously? And when he had told Goodison he was there to ask about Thomas Warren, what was behind that exhalation he gave, the flicker in his eyes? Relief, perhaps?

Lockhart has the feeling he used to get when they visited Midlothian when he was small, him and his mum and dad and his big and little sister. They would stay with Aunty Meg and Uncle Richard, and Uncle Richard would wrestle with him on the carpet and Aunty Meg never said a word and the meals were always fun and noisy as neighbours would come in and his mother would always be very quiet on those trips. He and his sisters would sleep in a tiny box room on blow-up beds, next to Aunty Meg and Uncle Richard’s bedroom, and he would hear raised voices late at night. Once, on the long drive home, he said to his mother, ‘Mum, do you like going to Scotland?’

He saw his parents turn their heads slightly as if they were exchanging a look, and then his mum said, ‘Of course, Akash, I love Scotland, it’s beautiful.’ There was a silence then, as if his parents were thinking something through between the two of them. After a while, his father said, ‘Aunty Meg and Uncle Richard have had a few problems, Akash, so that’s why things sometimes seem a bit funny up there. It’s grown-up stuff.’

The following year, his mother told him that Aunty Meg and Uncle Richard didn’t live together any more and that Uncle Richard had been very nasty to Aunty Meg, so nasty that it went to court and a judge said he was lucky not to be sent to prison.

He had a funny feeling then, a feeling of not being told the whole story but of not really wanting to know, because it was dark and complicated and adult and however much he wanted to be grown up – principally, so he could drive a car – there were still things in the dark and complicated adult world that he knew, instinctively, he was not yet ready to know.

And he has the same feeling now, that he doesn’t really want to know more, because a young woman is dead and PC Akash Lockhart from the British Transport Police knowing more about why she is dead won’t bring her to life again, after all. And shouldn’t he be concentrating on the prevention of future crime, not worrying about one that a coroner said wasn’t even a crime, just some awful tragedy like all the other awful tragedies that happen? It isn’t in his interests to pursue this, not on any level. He just feels like it’s the right thing to do.