'No, for God's sake, no!' he screamed, and then his foot slipped and he was falling.

Helen looked down, saw a sudden stoppage of traffic, horns honking, the sound drifting up. She turned at once, went through the suite to the door, opened it and went out. A few moments later, she was descending to the foyer. She walked through to the ballroom, took a glass of champagne from a tray held by one of the waiters by the door, and mingled.

Nemesis was the right word. It hadn't needed her on this occasion. Cohan had paid an inevitable price. Everything came around, a law of life. She hadn't needed to do it herself, only that it should be done. It was enough. She saw a great deal of movement down at the main door, caught a glimpse of Ferguson and Dillon and then was aware of a pain in her chest. She found her pill box, swallowed two with a gulp of champagne and walked towards the ballroom entrance.

'Perhaps he's gone up to his suite,' Dillon said as they finished their search of the ballroom, and then there was the sound of horns from outside the ballroom, a considerable disturbance. Hannah said to Ferguson, 'I'd better see what the trouble is, sir.' The traffic had slowed noticeably, and Hannah immediately saw the cause of it. There were people on the pavement surrounding a body, and a single motorcycle cop was standing beside his machine and calling it in. Hannah flashed her ID.

'Chief Inspector Bernstein, Special Branch. What happened?'

'I was just passing, guv. He fell from up the top, nearly hit a passing couple. The woman is in shock over there. I've called an ambulance and backup.'

Hannah leaned down and recognized Cohan at once. She straightened. 'I know this man, Constable, he's a guest at the hotel. You stay shtum , no answers to any questions, not to the press, not to anyone. This is a red alert. You know what that means?'

'Of course I do, guv.'

'I'm going inside, but I'll be back.'

They checked out Cohan's suite, the three of them, with a decidedly shaken duty manager. Hannah said, 'Not a thing, no sign of a struggle.'

'I agree, Chief Inspector,' Ferguson said. 'But did he fall or was he pushed?' He turned to Dillon. "What do you think?'

'Oh, come on, Brigadier, who believes in coincidence in our business?'

'Yes, I agree.' Ferguson nodded. 'She must be one hell of a woman.'

'I'm inclined to agree,' Dillon nodded.

Ferguson said to the duty manager, 'Keep this suite locked and secure. You'll have police here to do forensic tests quite soon.'

'Of course, Brigadier.'

Ferguson turned to Dillon. 'You break the bad news to Blake, and obviously through him, to the President. I'll handle the Prime Minister.'

'The great pity it is, your knighthood going down the drain like this,' Dillon said.

Ferguson smiled. 'I always knew you were on my side, Dillon.'

In spite of the close proximity of the house in South Audley Street, Lady Helen had arranged for Hedley to wait for her in Park Lane in the Mercedes. She pushed her way out through the curious onlookers, passing what was left of Senator Michael Cohan. Hedley saw her coming, jumped out and got the rear door open. She got in, he climbed behind the wheel and drove away.

'Just drive around, Hedley, it's been a heavy night.' She lit a cigarette.

'What happened?'

She told him everything. 'So, Cohan's gone and I'm actually left with a link with Jack Barry.' She held up the mobile. 'I'll try him again, shall I?'

Barry grabbed at the phone when it rang. 'Who is this?'

'Nemesis,' she said. 'But first, some hot news. Senator Michael Cohan took a fall from the seventh floor of the Dorchester in Park Lane. I'm using his mobile.'

More than at any time before in his life, Jack Barry was shaken rigid. 'What are you telling me?'

'That Senator Michael Cohan is lying on the pavement in Park Lane outside the Dorchester Hotel. It's like a bad Saturday night in Belfast. Police, ambulances, onlookers, but then you know about this kind of thing.'

Strangely enough, Barry wasn't angry. He actually knew a kind of fear. 'Who in the hell are you?'

'Brady, Kelly, Cassidy in New York, Tim Pat Ryan in London, and now Senator Michael Cohan. That's who I am.' She laughed. 'That just leaves you and the Connection.'

Barry took a deep breath. 'Okay, so who are you? Loyalist freedom fighters? Red Hand of Ulster? Protestant scum?'

'Actually, it may surprise you to know that I'm a Roman Catholic, Mr Barry. Religion doesn't come into it and I'm surprised you say Protestant scum. You're a Protestant yourself.

So was Wolfe Tone, who invented Irish Republicanism; so was Parnell, who came close to achieving a United Ireland.' She was enjoying herself now. 'Then there was Oscar Wilde, George Bernard Shaw, Sean O'Casey, all Prods.'

He cut in, angry now. 'What kind of shite is this? I don't need a fugging history lesson. What's it about? Who are you?'

'The woman who is going to execute you, just like I executed the others. Justice, Mr Barry, is what it's about, a rare commodity these days, but I intend to have it.'

He listened to her soft, measured voice, entirely the wrong kind of voice for what he was hearing. His anger increased. You're mad.'

'Not really. You butchered my son in Ulster three years ago, and executed his friends, four of them, including a woman. You wouldn't remember, Mr Barry, I'm sure. You've got so much blood on your hands, it's hard to remember which corpse is which.' She was giving him too much information, but it was all right. A plan was forming in her mind.

Barry had never felt so frustrated. 'Look, Cohan's mobile is to use to you. It's coded. Any calls are untraceable.'

"Yes, but I can at least speak to you.'

"Okay, so what is it you want?'

"It's quite simple. As I said, you butchered my son in Ulster three years ago. I'm going to butcher you.'

He felt a sudden touch of fear again. 'No way. You're crazy, lady!'

'At least I can talk to you when I want on this very useful bone. We could even arrange a meeting. I'll be in touch.'

'Anytime, you bitch. You got a time and place, just name it,' but she had already rung off.

Lady Helen said, 'Pass me the flask, Hedley.' He did so. She took a swallow and passed it back. 'Excellent. I feel great.' She got out her silver case, lit a cigarette and inhaled deeply. ' Marvellous. Drive round for a while. The Palace, Pall Mall.'

The rain had increased again, the wipers clicked backwards and forwards. Hedley cruised the traffic carefully.

'I like driving in the rain,' she said. 'It's a safe, enclosed feeling. It's as if the rest of the world doesn't exist. Do you like the rain, Hedley?'

'Rain?' He laughed out loud. 'Lady Helen, I saw too much of it in ' Nam. Patrolling in the swamps of the Mekong Delta, leeches applying themselves to your more important bits and those monsoon rains sluicing down.'

'Just hearing about it makes me shiver. Find a pub. I feel like a drink.'

Which he did, a very respectable place called the Grenadier close to St James's Place. They'd used it before. The landlord, Sam Hardaker, was an old Grenadier Guards sergeant and knew Hedley from his days at the Embassy.

'A real pleasure, Lady Helen.'

'Nice to see you, Sam. I don't expect you have such a thing as a bottle of champagne?'

'One in the fridge. Non-vintage, but Bollinger. Promised to a Grenadier Guards officer at the Palace, but he'll have to do without.'

She and Hedley sat in a corner booth, Sam brought the Bollinger in a bucket and produced two glasses. He uncorked and poured. Lady Helen tasted it.

'Heavenly.' She smiled as Sam filled the glasses. 'They say that if you're tired of champagne, you're tired of life.'

'I wouldn't know,' Sam said. 'Being a beer man myself.'

He retired and she lit another cigarette. 'All right, Hedley?'