‘I understand.’

‘No, you don’t. You’ve been in this house, this house where you would never have been welcome, and you’ve lied and you’ve lied. How can you do that? How are you so good at that?’

‘I’m sorry I lied. But I was looking after your children like anyone would look after them.’

Bridget gave a bitter shout of laughter. ‘Are you insane? Is that your line of defence? I’ve never met anyone like you. You’re off my scale.’ She took a few deep breaths, as if she were trying to calm herself down. ‘Let’s go out into the garden. I feel trapped in here, as if I’m going to explode with something.’

Bridget and Al’s home was just a medium-sized terraced house, but when they stepped into the garden, Frieda felt as if they were stepping into a park. The garden was narrow but quite long and there were gardens on either side and another row of gardens at the far end. There were huge plane trees and a birch and fruit trees, all hidden from the streets that surrounded them. Bridget led them along a path to a paved area with a wooden table surrounded by metal chairs.

Frieda sat on one. It felt cold even on this sunny morning. ‘Why haven’t you called the police?’ she asked.

‘I’m asking the questions, not you.’

‘All right.’

‘I wasn’t asking for permission. And I’m on the brink of calling the police. But I wanted to talk to you myself first. You’ve been going through our stuff. At first I couldn’t believe it. Things had been moved around – at least, I thought they had. But nothing was gone. I just had to be sure. Now I am. You’re the woman Sandy’s friends hated. You’re the woman who’s wanted for his murder. And you’re in my house, looking after my children.’

‘Yes.’

‘It’s your turn. Did you kill Sandy?’

‘No.’

‘Why should I believe you? The police obviously don’t.’

‘If I’d killed him, I wouldn’t be here trying to find his murderer.’

‘So that’s what you’re doing, is it?’

‘Yes.’

‘You would say that.’

Frieda shrugged. ‘Perhaps. But it’s true. That’s all I can say. I did not kill Sandy.’

‘And why here, in our house? What are you doing? What the fuck are you doing, Frieda fucking snoop Klein?’

‘You and your husband weren’t just friends with Sandy.’

‘Oh, weren’t we?’ Bridget folded her arms across her chest and glowered.

‘What was the problem that Al had with Sandy? The one he was complaining about.’

An expression of distaste appeared on Bridget’s face ‘Go on,’ she said.

‘What do you mean?’

‘I’ll answer your question, but only after you tell me – truthfully – how you know that Al was having a problem with Sandy.’

‘Because I read his emails.’

‘Do you never think about people’s privacy?’

‘Not when somebody has been murdered. Not when I’ve been accused of killing him.’

‘So you read through Al’s emails. And?’

‘Is it true that Al was angry with Sandy?’

‘Disappointed.’

‘He seemed extremely disappointed in the message I read.’

‘Sandy was shaking up the department. One thing he did was to shut down a research project that some of Al’s Ph.D. students were working on.’

‘Was he being unfair?’

Bridget shrugged. ‘Who knows? I suppose it was Sandy’s job to make decisions like that and it was Al’s job to feel a bit aggrieved about it. He was pissed off, he probably slammed a few doors, but he wasn’t going to kill Sandy because of it.’

‘You’d be surprised at the little things that would make someone kill someone else.’

‘You learned that as a therapist?’

‘Partly.’

‘Al couldn’t do something like that.’

Frieda didn’t reply.

‘I know that you’re going to say that anyone could do it. But he didn’t.’ Bridget paused, then began again in an angry tone: ‘Anyway, why am I defending myself to you? I just need to pick up the phone and the police will be here in two minutes and they’ll lock you up. Or are you going to stop me somehow?’

‘I’m not going to stop you,’ said Frieda. ‘If you want to call them, I’ll just sit here.’

Bridget glared at her. ‘Before I call them, is there anything you want to tell me or ask me?’

‘The police searched my house. They found Sandy’s wallet hidden in a drawer. Somebody must have put it there. Someone with a key to my house. Not many people have a key to my house. But you do.’

‘Do I? I didn’t know that.’

‘Do you want me to show you?’

‘You probably know more about what’s in my house than I do. I suppose you mean the keys I got from Sandy.’

‘Yes.’

‘And you want me to explain why I’ve got them.’

‘Yes.’

Suddenly Bridget laughed. ‘Let me get this straight. At the time you were wandering around South London with our tiny children while the police were hunting for you, you thought that Al, or maybe even Al and I together, like some kind of Bonnie and Clyde, murdered Sandy because of an argument in the office. And then, having killed him and disposed of the body, we decided to plant evidence in the house of his ex-lover, someone we’d never met and knew almost nothing about. Is that right?’

‘That was one possibility.’

Bridget looked around the garden as if she were only noticing it for the first time. ‘About three months ago, it was around one o’clock in the morning and I was sitting here. I was wearing a sweater, a thick jacket and woolly hat. And Sandy was sitting where you’re sitting now.’

‘At one in the morning?’

‘We talked here for a bit and then we started to feel cold. We felt we needed to move around. So we walked out of the house and down to Clapham Road and then we walked around the Common for an hour, I think, maybe more.’

‘Were you having an affair?’

Bridget flinched. ‘That’s the sort of moment when someone would slap you round the face. I was going to say “Carla”. It’s hard to shed an old habit. Frieda Klein. Frieda fucking Klein.’

‘Were you?’

‘He knocked on the door after midnight and woke me up. Al is a heavy sleeper. He was apologizing. He knew about the children and how little sleep we were getting. He said he was thinking of doing something stupid and he needed to talk to someone and I was the only person he could think of.’

‘You mean …’

‘You know what I mean.’

‘Yes. He was contemplating suicide.’

‘So we talked. He said a lot and I said a bit. Mainly I listened. Then he went home. But he gave me a set of keys, just in case. The ones you found.’

‘What did he tell you?’

‘Mainly it was that he’d come back from the States for a relationship that had fallen apart and he didn’t think he was managing his life properly and he couldn’t see a way forward.’ She gave Frieda a look that had a flash of anger in it. ‘But I suppose you’re used to people lying on your couch and saying things like that to you.’

‘I don’t have a couch. What did you reply?’

‘Nothing clever. I said that it was hard to believe but it would pass. He just had to wait and trust in his friends.’

Frieda felt a pang. She should have been the one telling Sandy that. It was good advice and, in the end, that was what a lot of therapy for troubled people came down to. Just wait: gradually the pain will change and become more bearable. But she had been the cause of the pain.

‘Was it just once?’

‘It was only that extreme just the once. But we talked from time to time. Sometimes he would phone late at night.’

‘After all that, after all you did for him, wasn’t it a bit strange that he damaged Al’s career?’

‘Are you serious?’ said Bridget, in a tone of contempt that made Frieda wince. ‘You think we’re like that: I help you out when you’re in distress and, in return, you do my husband some kind of favour at work.’

‘He may have been trying to prove something.’

‘Like what?’

‘It can be difficult to be helped, to feel that someone has rescued you.’

‘You sound like you’ve got quite a low opinion of humanity.’