It was a crisp autumnal afternoon, with a clear blue sky. Some people were wearing coats or heavy jackets, and as they got further into the centre of Manhattan everyone looked as if they were in a hurry. Half the men scurrying past were dressed in suits with tieless shirts and wore worried frowns. Most of them had a mobile clamped to one ear and carried in their other hand a Starbucks coffee with a brown collar around it, as if that was a mandatory totem.

‘So, Pat and I, we worked out a pretty good programme for you,’ Dennis said.

‘Yeah,’ Pat confirmed. ‘Although we’re now working for the DA we’re happy to run you around as a favour for a friend and a fellow cop.’

‘I really appreciate it. I spoke to my FBI guy in London,’ Grace replied. ‘He knows I’m here and what I’m doing. If my hunches work out, we may well have to come back formally to the NYPD.’

Dennis hit the horn at a black Explorer in front of them that had put its flashers on and half pulled over, looking for something. ‘Fuck you! Come on, asshole!’

‘We’ve booked you into the Marriott Financial Center – that’s right down by Ground Zero, in Battery Park City. Figure that’ll be a good base, as we can get to most places you might want to check out easily enough from there.’

‘Give you some atmosphere too,’ Dennis said. ‘It was badly damaged. All brand new now. You’ll be able to see the work going on at Ground Zero.’

‘You know they’re still finding body parts,’ Pat said. ‘Six years on, right? Found some last month on the roof of the Deutsche Bank Building. People don’t realize. They got no fuckin’ idea the force of what happened when those planes hit.’

‘Right opposite the Medical Examiner’s Office they got a tented-off area with eight refrigerated trucks inside,’ Dennis said. ‘They’ve been there for – what – six years now. Twenty thousand unidentified body parts in there. Can you believe that? Twenty thousand?’ He shook his head.

‘My cousin died,’ Pat went on. ‘You knew that, right? He worked for Cantor Fitzgerald.’ He held up his wrist to reveal a silver bracelet. ‘See that, it has his initials. TJH. We all got one, wear it in his memory.’

‘Everyone in New York lost someone that day,’ Dennis said, swerving to avoid a jay-walking woman. ‘Shit, lady, you want to know what the fender of a Crown Victoria feels like? I can tell you, it don’t feel too good.’

‘Anyhow,’ Pat said, ‘we’ve been doing as much as we could before you got here. We checked out the hotel where your Ronnie Wilson stayed. Same manager’s still there, so that’s good. We’ve fixed for you to meet him. He’s happy to talk to you, but there’s no change from what we already know. Some of Wilson’s stuff was still in his room – his passport, tickets, a few underclothes. That’s all now in one of the 9/11 victim storage depots.’

Grace’s phone rang suddenly. Excusing himself, he answered it. ‘Roy Grace?’

‘Yo, old-timer, where are you now? Having an ice cream on top of the Empire State Building?’

‘Very droll. I’m actually in a traffic jam.’

‘OK, well, I have another development for you. We’re working our butts off here while you’re having fun. Does the name Kather-ine Jennings ring a bell?’

Grace thought for a moment, feeling a little weary, his brain less sharp than usual after the flight. Then he remembered. It was the name of the woman in Kemp Town that the Argus reporter, Kevin Spinella, had given him. The name he had passed on to Steve Curry.

‘What about her?’

‘She’s trying to sell a collection of stamps worth around four million pounds. The dealer she’s gone to is Hugo Hegarty and he recognizes them. He hasn’t seen them yet, only spoken to her over the phone, but he’s convinced, all bar a few that are missing, that these are the stamps he purchased for Lorraine Wilson back in 2002.’

‘Did he ask the woman where she got them from?’

Branson repeated what Hegarty had told him, then added, ‘There’s a serial on Katherine Jennings.’

‘Mine,’ Grace said. He fell silent for some moments, thinking back to his conversation on Monday with Spinella. The reporter had said Katherine Jennings seemed agitated. Would having four million pounds’ worth of stamps in your possession make you agitated? Grace reckoned he’d be feeling pretty relaxed, having that kind of loot, so long as it was in a safe place.

So what was she agitated about? Something definitely smelled wrong.

‘I think we should put surveillance on her, Glenn. And we have the advantage of knowing where she lives.’

‘She may have done a runner from there,’ Branson replied. ‘But she’s made an appointment to go to Hegarty’s house tomorrow morning. And she’s bringing him the stamps.’

‘Perfect,’ Grace said. ‘Get on to Lizzie. Tell her we’ve had this conversation and I’m suggesting trying to get a surveillance team to pick her up at Hegarty’s house.’ He looked at this watch. ‘There’s plenty of time to get that in place.’

Glenn Branson looked at his watch too. It wasn’t going to be a simple matter of a two-minute call to Lizzie Mantle. He was going to have to write out a report detailing the reasons for requesting a surveillance unit and its potential value to Operation Dingo. And he was going to have to prepare the briefing. He wasn’t going to make it home for hours yet. It would mean another bollocking from Ari.

Nothing new there.

When Roy Grace ended the call, he leaned forward. ‘Guys,’ he said, ‘do you have someone who can put together a list of stamp dealers here?’

‘Starting a new hobby, are you?’ quipped Dennis.

‘Just stamping out crime,’ Grace retorted.

‘Shit, man!’ Pat said, turning to face him. ‘Your jokes don’t get any better, do they?’

Grace smiled sardonically. ‘Sad, isn’t it?’

The air stewardess was going through the safety demonstration. Norman Potting leaned over to Nick Nicholl, seated next to him near the rear of the 747, and said, ‘It’s all a load of rubbish, this safety stuff.’

The young Detective Constable, who was terrified of flying but hadn’t wanted to admit that to his boss, was hanging on to every word that was coming out through the speakers. Turning his face away to avoid the full blast of Potting’s bad breath, he peered upwards, working out exactly where his oxygen mask would be dropping from.

‘The brace position – you know what they don’t tell you?’ Potting went on, undeterred by Nicholl’s lack of reaction.

Nicholl shook his head, now watching and memorizing the correct way to tie the tapes on the life jacket.

‘It might save you in some situations, I grant you. But the thing they don’t tell you,’ Potting said, ‘is the brace position helps preserve your jawbone intact. Makes identifying all the victims from their dental records much easier.’

‘Thanks a lot,’ Nicholl muttered, observing the stewardess now pointing out where he would find his whistle.

‘As for the life jacket, that’s a laugh, that is,’ Potting carried on. ‘Do you know how many passenger airliners in the entire history of aviation have ever successfully made an emergency landing on water?’

Nick Nicholl was thinking about his wife, Julie, and his small son, Liam. He might never see either of them again.

‘How many?’ he gulped.

Potting touched the tip of his own thumb with his index finger, forming a circle. ‘Zero. Zilch. Nada. Not one.’

There’s always a first time, Nicholl thought, clinging tightly to the thought; clinging to it as if it were a liferaft.

Potting starting reading a men’s magazine he had bought in the airport. Nicholl studied the laminated safety card, checking the position of the nearest exits, glad to see that they were only two rows behind him. He was glad too that he was near the rear of the plane; he remembered a newspaper account of an air disaster in which the tail section broke off and all the passengers inside it survived.