Bell smiled. 'There's a third way.'

There was silence. It was Kate who said, 'What, for God's sake?'

Bell was enjoying himself. 'Well, to shoot the President of the United States should be an impossibility- or could it be absurdly simple?' He opened his briefcase and took out a magazine. He held it up. 'America, like Britain, is a democracy. You can write anything you want about the great and the good. There's an article in here on Jake Cazalet, everyone's favourite President. It was in my head, so I looked it up, and it's all I need for a general plan. Now I only need to finish working out the details.'

The silence was profound. He smiled, feeling his power. 'I think I'd like a large Bushmills Irish whiskey and then we'll talk.'

A few minutes later, he stood on the terrace looking down at the traffic while Paul Rashid read the article, then passed it to the others.

'All right,' Paul said. 'Now, tell us your plan, Mr Bell.'

'As the article says, Jake Cazalet loves to spend his weekends at that old beach house on Nantucket. They helicopter him straight from the White House lawn to the house late Friday, and he spends Saturday and Sunday there before coming back Sunday night. He has no family, just that one daughter in Paris.

'Cazalet doesn't like a big fuss: he's notorious for it. At the house, even the cook and the housekeeper come in on a daily basis; they live in town. There are staff quarters, but he refuses to have more than two Secret Servicemen there at the weekend. I did a little extra research and learned that one is called Harper, he's the communications officer. The other is his favourite, a big, black, former Marine named Clancy Smith, who served in the Gulf War. Smith is devoted to Cazalet. He'd step in the way of the bullet if he had to. And then there's Blake Johnson.'

'Yes, the article mentions him. It says he is the Director of something called the General Affairs Department at the White House,' Rashid said.

'Known as the Basement, because that is where it is. In actuality, it's the President's private hit squad, totally separate from the CIA, the FBI or the Secret Service. It's been passed on from President to President for at least twenty years, no one knows quite how long. Johnson is also Cazalet's closest friend, a Vietnam vet with a strong record.'

'And you're sure of all this?' George Rashid said.

'I have to be. It's why I'm still alive.'

'Okay, so we've got a down-to-earth President who doesn't want a fuss and likes to be on his own,' said Paul. 'You know damn well that the perimeter of that area will be well monitored by the Secret Service.'

'Exactly.' Bell opened the briefcase again, took out a map and unfolded it. 'See, from the President's house we have a seafront of beach and sand dunes. But at the rear, we have this area of marsh, very unusual for Nantucket; it's the only spot like it on the island. It stretches in quite a way: high reeds, water, mud, a paradise for bird watchers. Cazalet loves it. Goes for a run along the paths every morning with his dog, and good old Clancy Smith running behind. Smith has a gun under his left arm and an earpiece, naturally, but there's no one else around, unless his friend Blake Johnson happens to be there that weekend and decides to join in the fun. If he turns up, I'll stiff him, too.'

There really was a heavy pause now and it was Kate who said, 'Everything you say makes sense, but there would be no way you would get inside the perimeter, inside the marsh.'

Bell smiled. 'Sorry, I haven't explained. You, my lord, have a house on Long Island, I believe?'

'That's right.'

'You'll supply me with a boat – a Sport Fisherman will do – and someone to pilot it. We'll sail up to the area and drift around a mile or so offshore. You'll also find me a Dolphin Speed Trailer. Those things have two large batteries and travel underwater. Liam and I will go scuba diving, something we're good at, and then invade the marsh underwater into the reeds.'

'Then what?' Michael Rashid asked.

'Then wait for Cazalet, shoot him and Clancy Smith, and bugger off out of there. It'll take a little while for Harper to wonder why he hasn't heard anything and in that time we'll return with the Dolphin to the Sport Fisherman, then get back to Long Island, where you'll have a Gulfstream waiting to get us the hell out of there and onwards to Shannon.'

He paused, emptied his glass then said to Paul Rashid, 'Will it do?'

Rashid said calmly, 'I think it will do very well.' He turned to his brother George. 'Another Bushmills for Mr Bell.'

It was Kate who said, 'That's quite a script, but what if the script goes wrong? What if it doesn't work?'

'Nothing is certain in this life,' said Bell. 'There'll be dicey bits, but if we prepare this properly, it should work.'

'Then see that you do prepare properly,' said Paul. 'Remember, we'll only get one chance at this. If you fail, Cazalet's security will become so heightened it'll be impenetrable. And then we'll have to go through the trouble of finding another target.'

'Another target?' said Michael.

'I told you, brother. One way or another, someone is going to pay.'

There was silence. Then Bell turned to Kate. 'Will you be handling the organization of what we need?'

She glanced at Paul, then nodded. 'Anything you want.'

'All right. The Sport Fisherman I've already mentioned, the Dolphin Speed Trailer, diving equipment for two.'

'Weaponry?' Paul Rashid asked.

'I prefer basic AK assault rifles, with silencers. A couple of Brownings with Carswell silencers. That's all. Very simple, if things go well.'

'You said if again,' Kate told him.

Bell smiled. 'Oh, Lady Kate, I've been at it for twenty-eight years, and if you knew how often the best-laid schemes go wrong, you'd understand why I'm a cynic. Now' – Bell took a card from his pocket – 'your one hundred thousand pounds was nice, but I want the next instalment now. That's my Swiss bank account. One million on deposit against the three.'

Paul Rashid nodded. 'Of course.' He took the card and passed it to Michael. 'See to it.' He smiled. 'Champagne is indicated, I think.'

'A nice thought.' Bell smiled. 'But it's the last time. Once I start working, I stop drinking.'

'Well, that seems sensible.'

Kate offered champagne all round. Rashid raised his glass. 'So, we change the world.'

Bell laughed out loud. 'God bless, ould son, but if you believe that, you'll believe anything.'

Two days later, Kate Rashid took Bell and Casey down to the pier at Quogue, where they found a Sport Fisherman named Alice Brown and a man named Arthur Grant, who was fiftyish, with greying hair tied behind his neck.

'Mr Grant,' Kate said, 'these are the gentlemen I spoke about. They want a run up to Nantucket, to do a little diving. Mr Bell is looking for some interesting wrecks. You already have the Dolphin on board.'

Grant poured himself a Jack Daniel's. 'Well, lady, that's your story. Me, I think maybe they're up to something more than interesting wrecks, but I don't give a damn. Twenty thousand bucks, and she's yours.'

'Agreed.' She turned to Bell. 'Keep in touch,' and she went up the companionway.

Grant said, 'She's got a great ass on her.'

Bell dropped the bag containing the weaponry and kicked him on the right shin, then swung him around and Casey head-butted him. Grant fell back across onto the deck and Bell leaned over.

'From now on, you belong to me, Grant. Do we understand each other? Watch your mouth, do your job and you'll get the twenty grand. Otherwise -'

He nodded to Casey, who took a knife from his pocket, pressed a button and the blade jumped up.

'I'm sorry,' Grant said.

'Well, remember you're sorry,' Bell told him.

In London, Ferguson sat in his office at the Ministry of Defence working through papers. Detective Superintendent Hannah Bernstein came in.