Farlowe relaxed in his armchair and Banks took the swivel chair in front of the writing desk. One sniff of the clean, leather-scented air tipped him off that this was a non-smoking room.

‘We’re very grateful for the information you gave us,’ Banks began, ‘but I was wondering if you remembered anything else about that evening.’

Farlowe, a small, roly-poly man with tufts of grey hair over his ears, still wearing a three-piece suit, pressed his damp lips together and scratched the side of his nose. Finally he shook his head. The roll of pink fat around his neck wobbled. ‘Can’t say as I do, no.’

‘Do you mind if we go over a couple of points?’

‘Not at all. Be pleased to.’

Banks sipped some wine and asked about the timing.

Farlowe strained to remember for a moment, then answered. ‘I know the first one, the man, called at about seven o’clock because we’d just had supper and I was in the front room turning the Christmas-tree lights on. Then I caught a glimpse of the woman standing on the doorstep when I went to replace a burnt-out bulb a bit later. The door was open and she was talking to the Hartley woman.

‘Did you get a clear look at her?’

‘No. She had her back to me. Nicely shaped, though.’

‘So there’s no doubt it was a woman?’

‘None at all.’

‘What was she wearing?’

He put a pudgy finger to his lips and whistled while trying to recall the scene. ‘Let me see… It was a winter jacket of some kind, padded or thickly lined. Waist-length, no longer, because I could see the outline of her hips That’s how I knew it was a woman. A youngish one, I’d say. And she wore tight jeans. Lovely long legs she had. He winked.

‘What about her hair?’

‘It was wrapped in a scarf. I really couldn’t see it at all. And she was silhouetted by the hall light of the house, of course, so I couldn’t make out any detail. It was only a quick glimpse I got. I already told all this to your constable the other night.’

‘I know, and I’m sorry to put you through it again, sir Sometimes, believe it or not, people do remember more when they’re given a few days to think about it. What was Caroline Hartley wearing?’

‘As far as I could tell, it was some kind of bathrobe. She held it wrapped tight around her while she stood at the door, as if she was feeling the cold. I’m sorry I can’t be of any more help. I’d like to see the blighter caught, of course. Don’t like the idea of a murderer stalking the neighbourhood.’

‘The third visitor,’ Banks asked. ‘Can you be clearer about the time?’

‘I have given the matter some thought,’ Farlowe said, reaching for a decanter on the table beside him. ‘Port?’

Banks tossed back the rest of his wine and held his glass out. ‘Please. And…?’

‘I’m trying to recollect why I was at the front window again, but it’s slipped my mind. Perhaps I’d heard a noise or something…’ He tapped the side of head. ‘That’s it! I remember. I heard some music and I went out to see if we had carol singers in the street. Plagued by them we are.’ He made them sound like an infestation of rodents. ‘I consider I’ve handed out my fair share this year. Should be restricted to Christmas Eve, if you ask me. Anyway, it was only the wife, putting the radio on.’

‘Do you remember the time?’

‘No. All I remember, now I come to think about it, is hearing “Away in a Manger” and heading for the window. But there was no one at the door. I noticed a woman going into the house over the street, the house where the woman was murdered.’

‘Can you add anything to your earlier description?’

‘I’m sorry. It all happened so fast. I have to admit, I was rather angry at the thought of more singers and I just caught the figure out of the corner of my eye.’

‘But you’re sure it was a woman?’

‘Well, this one was wearing a light coat, belted, I think, because it came in at the waist, right down to mid-calves, and she definitely didn’t have any trousers on. I thought I could see the bottom of a dress or skirt, too, as if the coat was just a bit too short to cover the dress. And you could see her legs below that.’

‘What about height? Any idea?’

‘A little taller than the woman who answered the door, Caroline Hartley.’

‘Hair?’

He shook his head. ‘Again, her head was covered by a scarf of some kind.’

‘And this woman definitely entered the house?’

‘Oh, yes. She was walking in when I saw her.’

‘So you didn’t notice Caroline Hartley’s reaction to seeing her?’

‘No, not at all. I didn’t even see Caroline that time, just this other woman silhouetted as she walked in the door.’

‘So Caroline might not have let her in?’

‘I suppose that’s possible. But there didn’t seem anything suspicious about it. She didn’t seem to be pushing, and I didn’t hear any noise of forced entry or anything like that. It all seemed perfectly normal to me. I try to be a responsible neighbour. If I’d thought there was any trouble I would have called the police.’

‘Did you see her leave?’

‘No. But then I didn’t look out the window again. Anybody could have arrived or left between seven thirty and the time when… well, you know… and I wouldn’t have seen them.’

Banks finished his port and stood up. ‘Thank you for being so co-operative, Mr Farlowe. Also for the port. It was very good.’

Farlowe smiled. ‘Yes, it is, rather, isn’t it. The sixty-three vintage, you know.’ He struggled to get out of his armchair, floundering like a seal on a beach.

‘Please don’t bother showing me out,’ Banks said. ‘I’ll find my own way.’

‘Oh, very well. Fine, then. Bye.’ And Banks saw Mr Farlowe reach for the decanter again as he left the room. A suitable case for gout, that one. A lot of tipplers, it seemed, on Oakwood Mews.

On the way out, he met Mrs Farlowe in the hall. She had seen nothing that night, but she was able to tell him that the radio had been tuned to Radio Three, as always, when she turned it on. No, she couldn’t remember what time, but her husband was right. It was a carol service from King’s College. ‘Away in a Manger’ had been playing. Lovely tune, that one, isn’t it? Banks agreed and left.

From Mrs Eldridge at number eight Banks got no further information. She had seen the man go in first, then the woman knocking on the door at about seven fifteen. No, she hadn’t seen the man leave in the meantime, but the woman in the short coat and tight jeans definitely didn’t enter the house. And it wasn’t the same woman as the one who called later. This one was a bit taller and dressed differently. Some kind of long dress under her coat instead of jeans. The way it looked, unless Patsy Janowski had dashed off, changed clothes and added a few inches to her height in the interim, the third visitor couldn’t possibly have been her.

He needed to know who this third woman was. Unless someone else had come after her, someone nobody had seen arrive, or unless Claude Ivers had been in the house all the time and nobody had seen him leave, then she was the one, almost certainly, who had killed Caroline Hartley. Was it Veronica Shildon, as Susan had suggested? Banks didn’t think so – her love and grief seemed genuine – but he needed to talk to her again. There was a lot of ground yet to cover before he could hope to understand the people, and therefore the motives, involved in this case.

There was, however, one small, practical piece of information he carried away with him. Both Mr and Mrs Farlowe had said that the third woman entered the house – bidden or otherwise – when ‘Away in a Manager’ was being played on Radio Three. It should be possible to find out from the local BBC station what time the programme started, the order of carols in the concert and the length of each one. Given that information, it would be simple to work out at exactly what time the mysterious third woman had entered Caroline Hartley’s house and, in all likelihood, stabbed her to death with a kitchen knife.