‘Hard to miss what Mansour was shouting.’

‘That’s what I thought. Give me a sec.’

Bull took out his mobile phone and placed a call. It was answered on the first ring.

‘Kim, we need to cast a social media net. Everything from Flight PA16 to Stoke Newington Police Station and all terms in between. Err on the side of caution on this one, OK? Blanket coverage.’

Bull disconnected the call and turned back to Nelham.

‘Check your records, see if there’s any way to identify the civilian. If there is we can be more focused on any leaks that might come from that end. Keep me up to date.’

Bull turned back to face Sergeant Langley as Nelham moved away. He did not miss a beat.

‘What about other channels of enquiry? Who else has been officially spoken to about this? Which other agencies?’

‘Officially, guv? Just your boys. As soon as we confirmed that Mansour wasn’t a crank or some drunk, we followed normal protocol. I took the lead and I contacted SO15.’

‘So no one beyond my unit?’

‘Not by me.’

‘What about the US Secret Service?’

Langley’s brow furrowed in confusion at the question.

‘Yanks? I wouldn’t even know where to start.’

Bull experienced a moment of relief at his response. If the Secret Service was unaware of Mansour’s arrest – of his very existence – then Bull had the time he had hoped for. He could question Mansour without them breathing down his neck.

It would make his life a whole lot simpler, but there was still a difficult job to be done. And who knew how long the Americans could be kept in the dark.

‘So what do we know about Mansour?’ Bull asked.

‘Very little beyond the initial confession. He was a mess when he came in. Physically wiped out. He could hardly breathe and his blood pressure was through the roof. We had him checked out with the ME in case of a heart attack. But after that, once he was calm again? Nothing.’

‘What do you mean, “nothing”?’

‘I mean he hasn’t said a word. He won’t even confirm the name he gave us.’

‘Then how do you know he isn’t a crank? Do you know how many lunatics we have claiming credit for this sort of thing?’

‘I know. But we acted on what he had told us, and it gave us enough to take him seriously. Enough to bring you in.’

Bull was intrigued; all of this was news to him.

‘Tell me.’

‘We got his name and his address while he was still frantic, and so once he stopped cooperating we sent a couple of boys to the home – it’s minutes from here – and they found a body there. Young Arab guy, throat slit.’

‘Really?’ The information was not what Bull had been expecting. ‘Any idea who it is?’

‘Best evidence suggests the guy’s name was Bilal Essa. There were payslips in the place, from Pan-Atlantic Airlines. Suggests he was a baggage handler there.’