Sowerby said: 'Taken into care, I suppose, unless they can trace the father or the grandparents. He'll probably end up fostered or adopted. I wonder what the hell his mother thought she was doing.'

Harding spoke with sudden vehemence: 'Do they think? Ever? No faith, no stability, no family affection, no loyalty. They're blown like paper with every wind. Then when they do find something to believe in, something to give them the illusion that they're important, what do they choose? Violence, anarchy, hatred, murder.'

Sowerby looked at him, surprised and a little amused. Then he said: 'Ideas some of them think worth dying for. In that, of course, lies the problem.'

'Only because they want to die. If you can't cope with living look for an excuse, a cause you can kid yourself is worth dying for and indulge your death wish. With luck you can take a dozen or so poor sods with you, people who can cope with living, who don't want to die. And there's always the ultimate self-deception, the final arrogance. Martyrdom. Lonely and inadequate fools all over the world will clench their fists and shout your name and carry placards with your picture and start looking round themselves for someone to bomb and shoot and maim. And that girl, Amphlett. She hadn't even the excuse of poverty. Dad a senior army officer, security, a good education, privilege, money. She'd had it all.'

It was Sowerby who replied. He said: 'We know what she had. What we can't know is what she didn't have.'

Harding ignored him. 'And what did they expect to do with Larksoken if they did take it over? They wouldn't have lasted for more than half an hour. They'd have needed experts, programmers.'

Mair said: 'I think you can take it they knew what and who they'd need and had planned how they could get them.'

'Into the country? How?' 'By boat, perhaps.'

Sowerby looked at him and then said a little impatiently: 'They didn't do it. They couldn't have done it. And it's our job to see that they never can do it.'

There was a moment's silence, then Mair said: 'I suppose Amphlett was the dominant partner. I wonder what arguments or what inducements she used. The girl -Amy – struck me as an instinctive creature, not likely to die for a political theory. But that is obviously a superficial judgement. I only saw her once.'

Sowerby said: 'Without knowing them we can't be sure who was the dominant partner. But I'd say it was almost certainly Amphlett. Nothing is known or suspected about Camm. She was probably recruited as a runner. Amphlett must have had a contact in the organization, must have met him occasionally if only to receive instructions. But they'd be careful never to get in touch directly. Camm probably received the coded messages setting out time and place for the next meeting and passed them on. As for her reasons, she found life unsatisfactory no doubt.'

Bill Harding lunged over to the table and poured himself a large whisky. His voice was thick as if he were drunk.

'Life has always been unsatisfactory for most people for most of the time. The world isn't designed for our satisfaction. That's no reason for trying to pull it down about our ears.'

Sowerby smiled his sly superior smile. He said easily: 'Perhaps they thought that's what we're doing.'

Fifteen minutes later, Dalgliesh left with Mair. As they stood unlocking their cars he looked back and saw that the janitor was still waiting at the open door.

Mair said: 'Making sure that we actually leave the premises. What extraordinary people they are! I wonder how they got on to Caroline. There seemed no point in asking as they made it obvious that they had no intention of saying.'

'No, they wouldn't say. Almost certainly they got a tip-off from the security services in Germany.'

'And this house. How on earth do they find these places? D'you suppose that they own it, borrow it, rent it or just break into it?'

Dalgliesh said: 'It probably belongs to one of their own officers, retired, I imagine. He, or she, lets them have a spare key for such an occasional use.'

'And now they'll be packing up, I suppose. Dusting down the furniture, checking for fingerprints, finishing up the food, turning off the power. And in an hour no one will know that they were ever there. The perfect temporary tenants. They've got one thing wrong, though. There wasn't a physical relationship between Amy and Caroline. That's nonsense.'

He spoke with such extraordinary strength and conviction, almost with outrage, that Dalgliesh wondered for a moment whether Caroline Amphlett had been more than his PA. Mair must surely have sensed what his companion was thinking but he neither explained nor denied. Dalgliesh said: 'I haven't congratulated you yet on your new job.'

Mair had slipped into his seat and turned on the engine.

But the car door was still open and the silent warder at the door still waited patiently.

He said: 'Thank you. These tragedies at Larksoken have taken away some of the immediate satisfaction, but it's still the most important job I'm ever likely to hold.' Then, as Dalgliesh turned away, he said: 'So you think we still have a killer alive on the headland.'

'Don't you?'

But Mair didn't reply. Instead he asked: 'If you were Rickards, what would you do now?'

'I'd concentrate on trying to find out whether Blaney or Theresa left Scudder's Cottage that Sunday night. If either of them did, then I think my case would be complete. It isn't one that I'd be able to prove, but it would stand up in logic and I think that it would be the truth.'

Dalgliesh drove first out of the drive but Mair, accelerating sharply, overtook him on the first stretch of straight road and remained ahead. The thought of following the Jaguar all the way back to Larksoken was, for some reason, intolerable. But there was no danger of it; Dalgliesh even drove like a policeman, inside, if only just inside, the speed limit. And by the time they reached the main road Mair could no longer see the lights of the Jaguar in his mirror. He drove almost automatically, eyes fixed ahead, hardly aware of the black shapes of the tossing trees as they rushed past like an accelerated film, of the cat's-eyes unfolding in an unbroken stream of light. He was expecting a clear road on the headland and, cresting a low ridge, saw almost too late the lights of an ambulance. Violently twisting the wheel, he bumped off the road and braked on the grass verge, then sat there listening to the silence. It seemed to him that emotions which for the last three hours he had rigorously suppressed were buffeting him as the wind buffeted the car. He had to discipline his thoughts, to arrange and make sense of these astonishing feelings which horrified him by their violence and irrationality. Was it possible that he could feel relief at her death, at a danger averted, a possible embarrassment prevented, and yet, at the same time, be torn as if his sinews were being wrenched apart by a pain and regret so overwhelming that it could only be grief? He had to control himself from beating his head against the wheel of the car. She had been so uninhibited, so gallant, so entertaining. And she had kept faith with him. He hadn't been in touch with her since their last meeting on the Sunday afternoon of the murder and she had made no attempt to contact him by letter or telephone. They had agreed that the affair must end and that each would keep silent. She had kept her part of the bargain, as he had known she would. And now she was dead. He spoke her name aloud, 'Amy, Amy, Amy.' Suddenly he gave a gasp which tore at the muscles of his chest as if he were in the first throes of a heart attack and felt the blessed releasing tears flow down his face. He hadn't cried since he was a boy and even now, as the tears ran like rain and he tasted their surprising saltiness on his lips, he told himself that these minutes of emotion were good and therapeutic. He owed them to her and, once over, the tribute of grief paid, he would be able to put her out of his mind as he had planned to put her out of his heart. It was only thirty minutes later, when switching on the engine, that he gave thought to the ambulance and wondered which of the few inhabitants of the headland was being rushed to hospital.