He was a little late getting to Cricklewood, and it was ten past four when he walked up to the house and rang the bell. He rang Marty Foster’s bell first because there was a chance he might answer and he didn’t want to bother the Flynn girl unnecessarily. However, there was no answer. He tried again and again and then he rang the Flynn girl’s bell. Somehow it hadn’t crossed his mind there might be no reply to that either, that she could have forgotten her promise or simply be indifferent to her promise and go out. She hadn’t exactly promised, he thought with a sinking of the heart.

Of course a taxi could get him from here to Paddington in a quarter of an hour, there was nothing to worry about from that point of view. He stepped back and down and looked up at the windows which looked back at him like so many wall eyes. Maybe the bells weren’t working. He couldn’t hear any sound of ringing from outside. But the Flynn bell had been working on Monday . . .

Along the street the old deaf man was coming, a string bag in his hand containing some cans and a packet of tea. Alan nodded to him and smiled, and the old man nodded and smiled back in a way that was suspicious and ingratiating at the same time. Slowly he fumbled through layers of clothing to retrieve a key from a waistcoat pocket. He put the string bag down on the step and unlocked the front door.

Knowing it was useless to speak to him but feeling he must say something to excuse his behaviour, Alan muttered vaguely about people who didn’t answer bells. He edged past the old man into the passage and, leaving him on the doorstep wiping his feet, began to climb the stairs.

Immediately he heard the bell, the first time it rang, Nigel pointed the gun at Joyce and made her go into the kitchen. She understood this was because there was someone at the door he feared might be the police, but she didn’t reason that therefore he wouldn’t dare shoot her. There was something in his face, an animal panic, but the animal was a tiger rather than a rabbit, which made her think he would shoot her before he did anything else. He had taken off the safety catch.

He forced her into a chair and got behind her. Joyce slumped forward, the gun pressing against the nape of her neck. With his left hand Nigel felt about all over the draining board and the top of the bookcase and the drawer under the draining board for the rope. He found it in the drawer and wound it round Joyce as best he could, tying her arms to the back of the chair. When he had got the black stocking off his own bundle of notes, he put the gun down and managed to gag her. By then the doorbell had rung again and was now ringing in Bridey’s room. Nigel shut the kitchen door on Joyce and went back into the living room to listen. From downstairs he heard the sound of the front door being softly closed. No more ringing, silence.

Then footsteps sounded on the stairs. Nigel told himself they must belong to old Green. He told himself that for about two seconds because after that he knew that they weren’t the footsteps of a stout seventy-five-year-old but of a man in the prime of life. They came on, on, up to the bathroom landing and then up the last flight to the top. There they flagged and seemed to hesitate. Nigel went very softly to the door and put his ear against it, listening to the silence outside and wondering why the man didn’t knock at his door.

Alan hadn’t knocked because he didn’t know which was the right door. There were three to choose from. He knocked first at the door to the room on the side of the house, the detached side. Then he tried the door that faced it because the remaining door must be the one to the front room which was evidently occupied by Green. The old man was coming slowly and heavily up the stairs. Alan stepped aside and attempted some sort of dumb show to indicate whom he wanted, but how do you indicate Foster in sign language? The old man shook his head and unlocked the door at which Alan had last knocked and went inside, closing the door behind him. Alan tried the door to the front room. He waited, sure that he could hear on the other side of it the sound of someone breathing very close by.

Nigel put the gun in its holster underneath his jacket, and then he unlocked the mortice with the big iron key. There was only one man out there. Very probably he knew the room was occupied, so it might be less dangerous to let him in than keep him out. Nigel opened the door.

The man outside was in a suit and raincoat and carrying a briefcase, which Nigel somehow hadn’t expected. The face was vaguely familiar, but he immediately dismissed the idea that this might be the man he had seen watching the house. This was – he was convinced of it even before the brown envelope was produced – some canvasser or market researcher.

Alan said: ‘I’m looking for a Mr Foster.’

‘He’s not here.’

‘You mean he lives here? In there?’

A nod answered him. ‘I understood he was ill . . .’ Alan was almost deterred by the look on the handsome young face. It expressed amazement initially, then a growing suspiciousness. But he went on firmly. ‘I understand he was at home with the flu.’

At that the face cleared and the shoulders shrugged. Alan felt sure Marty Foster was somewhere in there. He hadn’t come so far to give up now, on the threshold of Foster’s home. The door was moving slowly, it was about to be shut in his face. Daring, amazed at himself, he set his foot in it like an importunate salesman, said, ‘I’d like to come in a minute, if you don’t mind,’ and entered the room, pushing the other aside, though he was taller and younger than he.

The door closed after him. They looked at each other, Alan Groombridge and Nigel Thaxby, without recognition. Nigel thought, he’s not a canvasser, he’s not from the hospital – who is he? Alan looked round the room at the tumbled mattress, the scattering of breadcrumbs on the seat of a chair, a plastic bag with knitting needles sticking out of it. Foster might be in whatever room was on the other side of that door.

‘I have to see him,’ he said. ‘It’s very important.’

‘He’s in hospital.’

From behind the door there came a thumping sound, then a whole series of such sounds as of the legs of a chair or table bumping the floor. Alan looked at the door, said coldly:

‘Which hospital?’

‘I don’t know, I can’t tell you any more.’ Joyce was working herself free of the rope which tied her to the chair, as Nigel had guessed she would. He put himself between Alan and the kitchen door, his hand feeling the holster round the gun. ‘You’d better go now. I can’t help you.’

It was twenty minutes to five. He was meeting Una at five, he was leaving London – hadn’t he done enough? ‘I’m going,’ Alan said. ‘Who’s behind that door, then? Your girl friend?’

‘That’s right.’

Alan shrugged. He began to walk back to the door by which he had entered as Nigel, striding to open it, called back over his shoulder:

‘OK, doll, one moment and you can come out.’

Alan froze. He had been pursuing one voice and had found the other – ‘Let’s see what’s in the tills, doll . . .’ He turned round slowly, the blood pounding in his head. Nigel was opening the door to the landing. Alan was a yard away from that door, perhaps only a hundred yards away from a phone box. He stopped thinking, speculating, wondering. He took half a dozen paces across that room and flung open the other door.

Joyce had got her arms free and was taking the gag off her mouth. He would hardly have known her, she was so thin and haggard and hollow-eyed. But she knew him. She had recognized the voice of the man she had supposed dead from the moment he first spoke to Nigel. She threw the black stocking on to the floor and came up to him, not speaking, her face all silent supplication.

‘Where’s the other one, Joyce?’ said Alan.