'What would that be?'

'Well, inextricably involved with the whole mess is the question of the Connection himself – the traitor in the White House.'

The chief of staff said, 'Yes, but nobody knows who it is.'

'Oh, we do,' Dillon said. 'We knew your investigation wasn't getting anywhere, Mr Thornton, so Blake mounted his own.'

Blake took a small tape recorder from his pocket. 'I had the Synod computer monitor telephone calls from the White House first, then Washington, to anyone named Jack Barry. The computer picks the name out, then we can retrieve the call.'

'And it worked?' said Cazalet.

'We have recordings of a number of calls, Mr President, but just one will do.'

He put the tape recorder on the balustrade and switched it on. The voice came through clearly. 'Lady Helen Lang. She's attending a big fat cat party in Long Island, so don't look for her at home.'

'I can wait,' Barry said. 'Don't worry. She's history.'

Blake switched off the recorder, and Cazalet turned in horror to his chief of staff. 'My God, Henry, that's your voice.'

Thornton seemed to sag, and leaned back against the balustrade, head down. He stayed that way, breathing deeply, and yet, when he looked up, his eyes were glittering.

'Why, Henry, why?' Jake Cazalet demanded.

'Let me answer that. Let's see if I can get it right,' Blake said to Thornton. 'Your mother had an illegitimate half-brother born in Dublin. He was a volunteer with Michael Collins in the Easter Rising in nineteen sixteen. Executed by the Brits.'

'Shot down without mercy,' Thornton replied. 'Hunted down like a dog. Seven bullets in him. My mother never forgot and I never forgot.'

'And when you were a postgrad at Harvard, there was a girl named Rosaleen Fitzgerald from Northern Ireland, killed in a firefight in Belfast,' Blake said. 'You loved her.'

'Murdered,' Thornton told him. 'By British soldiers. The bastards!'

Dillon jumped in. 'And years later, there you were, chief of staff at the White House, and all that juicy information started to roll in from British Intelligence and it was your chance for revenge,' he said. 'Up the rebels and Ireland must be free."

'How did you get mixed up with the Sons of Erin and Jack Barry?' Blake asked.

'Oh, that was Cohan. I was invited to a Sinn Fein fundraiser in New York, just as a guest. He was drunk. Rambled on about the diners club and how they all helped the glorious cause.'

'And Barry?'

'He was in New York on business to do with arms for the IRA. Brady, the Teamsters' Union guy, knew him and introduced him to the group. That's when they started calling themselves the Sons of Erin. Cohan boasted about it. A real-life gunman.'

'And how did you connect with Barry?'

'He was in New York during the early days of the peace process under his own name, all legitimate, staying at the Mayfair. His presence was mentioned in The New York Times. It was simple. I offered him information, nice and anonymous. Just a voice on the phone.'

'And then retribution struck.'

Thornton actually smiled. 'Isn't that the craziest thing you ever heard? I mean, a woman like her? Who would believe it?'

Cazalet turned to Blake. 'This is one hell of a mess. What are we going to do?'

At that moment, Thornton put a hand on the balustrade and vaulted over.

He landed on his hands and knees, and was up and running, unaware that Helen Lang stood in the shelter of the shrubbery nearby, and had heard everything.

'You've got nowhere to go, Henry,' Cazalet shouted, and followed Blake and Dillon down the steps.

Clancy Smith, alarmed by the shouting, flung open the study door and hurried through. ' Mr President?'

'Stay close, Clancy,' Cazalet called. 'This way,' and he ran after Dillon and Blake.

Clancy immediately called in a general alert to the rest of the Secret Servicemen on duty and went after them.

Helen Lang waited until they were well ahead, then followed cautiously.

There were many guests in the garden, those who'd come out with a glass in their hand to sample the view in the evening, and the sea beyond. One of them was Hedley. Concerned about Lady Helen, he'd taken off his chauffeur's cap and worked his way round to the garden at the rear of the house. Checked there by Secret Servicemen, his identification badge had sufficed and, of course, there were the other guests in the garden. It was simple chance that he'd seen Lady Helen by the terrace, had also seen the President outside the French windows, and had watched her go up the steps to speak to Cazalet.

He had no idea what was happening up there when Thornton, Blake and Dillon appeared, and he saw Lady Helen fade into the bushes. There was only the sound of the voices, and then Thornton jumped over the balustrade. The President and the others went after him. Of Lady Helen, there was no sign. Hedley followed in the direction she must have gone.

Thornton weaved his way through the shrubbery, dropped to one knee and paused. He felt at his waist for the pistol he'd stuck there earlier. He'd planned to use it on Helen Lang that evening, but now it would have other uses. There was a certain panic now. The Secret Servicemen, alerted by Clancy, trawled the garden, alarming the guests already disturbed by the shouts they had heard. Helen was close on his heels. She had followed him from that first moment when he had vaulted the balustrade, and ducked into the shrubbery so that the others didn't know where he'd gone.

What she didn't realize was that Hedley was close behind her. The sounds of pursuit faded, and she saw Thornton come out of the shrubbery in front of her and run, crouching, down to the water. He reached the wooden jetty by the boathouse, his running steps booming. He stopped at the speedboat and started to cast off the moorings, as Helen arrived.

' Mr Thornton,' she called.

Thornton paused, then turned, a Smith amp; Wesson in his hand. The image, the woman, standing in the diffused light, was enough.

'It's you, you bitch.'

'Yes, Mr Thornton, I'm afraid it is. Everything comes around. I believe you know what happened to my son. This is what you might call payback time.'

'Well, fuck you.' Thornton arced and aimed his Smith amp; Wesson.

Helen Lang reached in her bag to find the Colt.

Hedley, close on her heels, slid in the darkness, over the stern rail of the speedboat, moved in behind Thornton and slipped on the wet deck. Thornton turned, raised his weapon to fire, and

Helen shot him in the back of the head. Thornton went down on his knees and then fell forward. Hedley stood up.

'Wait for me in the parking area. I can handle this. Just go.'

She turned and ran.

Hedley had examined the description of Chad Luther's estate supplied by his corporation's London office, and knew that there was a reef at the entrance of the bay that was only negotiable at high tide. Now it was low. He shoved Thornton 's body over on to the stern deck, went into the wheelhouse and turned on the engine. When it was going well, he jumped to the jetty, cast off and let the speedboat go. When it hit the reef at the entrance of the bay, the force was so great that the speedboat bounced into the air and fireballed.

There were cries of alarm from guests in the garden, shouts as Secret Servicemen called to each other. Hedley stood in the bushes as the President arrived with Blake and Dillon.

'Oh, my God,' Cazalet called, staring out at the fire.

Hedley faded into the shrubbery and started back, and a moment later was aware of a sudden cry, a woman's voice. Helen's voice.

'Let me go!'

'I need to look in your purse, ma'am.'

It was Clancy Smith, holding her by the right wrist in the diffused light of a garden lamp.

Hedley moved in, grabbed Clancy by the arm and pulled him away. 'You leave her be, boy.'