A young white man was waiting for me by the back door. He was blond, with a broad open face and blue eyes. His suit, I noticed, looked tailored. But it was hard to tell since he’d obviously been wearing it for the last twenty-four hours straight. He was swigging from an Evian bottle which he lowered when he saw me, stuck out a friendly hand and introduced himself as DC Dominic Croft.

‘They’re expecting you,’ he said, but he didn’t say what for.

It was the cleanest nick I’d ever been in – it didn’t even have the distinctive smell of a lot of bodies working long shifts in heavy clothing that you expected in a working station. Eau de stab-vest, Lesley had used to call it. The place was painted exactly the same colour scheme as Belgravia and half-a-dozen other London nicks I’d been in – whoever was selling that particular shade of light blue must have been coining it.

‘This place is usually pretty empty,’ he said. ‘Normally it’s just the neighbourhood policing team.’

Dominic led me upstairs to the main offices where the air conditioning, such as it was, was failing to deal with the sheer mass of police. A couple of detectives looked up as we walked into the incident room, nodding at Dominic then pausing to give me a suspicious once-over before turning back to their work. They were all white and, between them and the press pack out the front, I suspected that on this case my diversity training had been wholly in vain.

Incident rooms during a major inquiry are rarely a barrel of laughs, but the atmosphere that day was grim, the faces of the detectives sweaty and intent. Missing kids are tough cases. I mean, murder is bad but at least the worst has already happened to the victim – they’re not going to get any deader. Missing kids come with a literal deadline, made worse by the fact that you don’t get to learn the timing until it’s too late.