No sane man. No sane man. Conklin sat slowly forward in his chair.

I'm not Cain. He never was. 1 never was! I wasn't in New York ...It was Carlos! Not me, Carlos! If what you're saying took place on Seventy-first Street, it was him! He knows!

But Delta had been at the brownstone on Seventy-first Street. Prints - third and index fingers, right hand. And the method of transport was now explained. Air France, Brevet cover ... Fact: Carlos could not have known.

Things come to me ... faces, streets, buildings. Images I can't place ...I know a thousand facts about Carlos, but I don't know why!

Conklin closed his eyes. There was a phrase, a simple code phrase that had been used at the beginning of Treadstone. What was it? It came from Medusa ... Cain is for Charlie and Delta is for Cain. That was it. Cain for Carlos. Delta-Bourne became the Cain that was the decoy for Carlos.

Conklin opened his eyes. Jason Bourne was to replace Ilich Ramirez Sanchez. That was the entire strategy of Tread-stone Seventy-one. It was the keystone to the whole structure of deception, the parallax that would draw Carlos out of position into their sights.

Bourne. Jason Bourne. The totally unknown map, a name buried for a decade, a piece of human debris left in a jungle ten years ago. But he had existed; that, too, was part of the strategy.

Conklin separated the folders on his desk until he found the one he was looking for. It had no title, only an initial and two numbers followed by a black X, signifying that it was the only folder containing the origins of Tread-stone.

T-7 X The birth of Treadstone 71.

He opened it, almost afraid to see what he knew was there.

Date of execution. Tarn Quan Sector. 25 March ...

Conklin's eyes moved to the calendar on his desk.

24 March.

'Oh, my God,' he whispered, reaching for the telephone.

Dr Morris Panov walked through the double doors of the psychiatric ward on the third floor of Bethesda's Naval Annex and approached the nurses' counter. He smiled at the uniformed aide shuffling index cards under the stern gaze of the Head Boor Nurse standing beside her. Apparently the young trainee had misplaced a patient's file - if not a patient - and her superior was not going to let it happen again.

'Don't let Annie's whip fool you,' said Panov to the flustered girl 'Underneath those cold, inhuman eyes is a heart of sheer granite. Actually, she escaped from the fifth floor two weeks ago but we're all afraid to tell anybody.'

The aide giggled: the nurse shook her head in exasperation. The phone rang on the desk behind the counter.

'Will you get that, please, dear,' said Annie to the young girl. The aide nodded and retreated to the desk. The nurse turned to Panov. 'Dr Mo, how am I ever going to get anything through their heads with you around?'

'With love, dear Annie. With love. But don't lose your bicycle chains.'

'You're incorrigible. Tell me, how's your patient in Five-A? I know you're worried about him.'

'I'm still worried.'

'I hear you stayed up all night.'

There was a three a.m. movie on television I wanted to see."

'Don't do it, Mo,' said the matronly nurse. 'You're too young to end up in there.'

'And maybe too old to avoid it, Annie. But thanks...'

Suddenly Panov and the nurse were aware that he was being paged, the wide-eyed trainee at the desk speaking into the microphone.

'Dr Panov, please. Telephone for...'

'I'm Dr Panov,' said the psychiatrist in a sotto voce whisper to the girl. 'We don't want anyone to know. Annie Donovan here's really my mother from Poland. Who is it?'

The trainee stared at Panov's I.D. card on his white coat; she blinked and replied. 'A Mr Alexander Conklin, sir.'

'Oh?' Panov was startled. Alex Conklin had been a patient on and off for five years, until they had both agreed he'd adjusted as well as he was ever going to adjust - which was not a hell of a lot There were so many, and so little they could do for them. Whatever Conklin wanted had to be relatively serious for him to call Bethesda rather than the office. 'Where can I take this, Annie?'

'Room One,' said the nurse, pointing across the hall. 'It's empty. I'll have the call transferred.'

Panov walked towards the door, an uneasy feeling spreading through him.

'I need some very fast answers, Mo,' said Conklin, his voice strained.

'I'm not very good at fast answers, Alex. Why not come in and see me this afternoon?' 'It's not me. It's someone else. Possibly." 'No games, please. I thought we'd gone beyond that.' 'No games. This is a Four-Zero emergency, and I need help.'

'Four-Zero? Call in one of your staff men. I've never requested that kind of clearance.' 'I can't. That's how tight it is.' 'Then you'd better whisper to God."

'Mo, please I only have to confirm possibilities, the rest I can put together myself. And I don't have five seconds to waste. A man may be running around ready to blow away ghosts, anyone he thinks is a ghost. He's already killed very real, very important people and I'm not sure he knows it Help me, help him]' 'If I can. Go ahead.'

'A man is placed in a highly volatile, maximum stress situation for a long period of time, the entire period in deep cover. The cover itself is a decoy - very visible, very negative, constant pressure applied to maintain that visibility. The purpose is to draw out a target similar to the decoy by persuading the target that the decoy's a threat, forcing the target into the open ... Are you with me so far?'

'So far,' said Panov. 'You say there's been constant pressure on the decoy to maintain a negative, highly visible profile. What's his environment been?' 'As brutal as you can imagine.' 'For how long a period of time?' Three years.'

'Good God,' said the psychiatrist. 'No breaks?' 'None at all. Twenty-four hours a day, three hundred and sixty-five days a year. Three years. Someone not himself.'

'When will you damn fools learn? Even prisoners in the worst camps could be themselves, talk to others who were themselves.' Panov stopped, catching his own words, and Conklin's meaning. "That's your point, isn't it?'

'I'm not sure,' answered the intelligence officer. 'It's hazy, confusing, even contradictory. What I want to ask is this. Could such a man under these circumstances begin to ... believe he's the decoy, assume the characteristics, absorb the mocked dossier to the point where he believes it's him?'

"The answer to that's so obvious I'm surprised you ask it. Of course he could. Probably would. It's an unendurably prolonged performance that can't be sustained unless the belief becomes a part of his everyday reality. The actor never off the stage in a play that never ends. Day after day, night after night.' The doctor stopped again, then continued carefully. 'But that's not really your question, is it?'

'No,' replied Conklin. 'I go one step further. Beyond the decoy. I have to; it's the only thing that makes sense.'

'Wait a minute,' interrupted Panov sharply. 'You'd better stop there, because I'm not confirming any blind diagnosis. Not for what you're leading up to. No way, Charlie. That's giving you a licence I won't be responsible for - with or without a consultation fee.'