With Cooper sitting in to observe, Fry began by asking Lowther to confirm his name, age and address. Then she looked at him, momentarily unsure how to approach the interview, to get him talking.

‘I gather your address is an apartment, sir?’

‘Yes, it’s a new development in Matlock. They converted an old will, I mean mill. It’s rather nice.’

‘I see. Do you own the apartment, Mr Lowther?’

‘It’s a nine-hundred-and-ninety-nine-year lease. With nine hundred and ninety-seven years left to run. Less two years, you see. But it’s no loss.’

Fry frowned. ‘Right. And you’re an actuary by profession?’

‘– confession? Yes, I have very intensive experience in the field.’

‘Do you?’

‘I worked in Leeds, in West Yorkshire, for three years. But I left that job a year ago.’

‘So you’re not employed at the moment?’

He smiled. ‘You might say I’m resting. There’s not so much work for actuaries around these ports.’

‘I see.’

Fry had never felt so unsure of anyone before. She could hear herself saying ‘I see’ too much, a clear indication to anyone listening that she hardly understood a thing that Lowther was saying. Did he recognize that, too? Was it a deliberate ploy on his part to disrupt her interview technique? If so, it was very subtle. But it was working.

Suddenly, Lowther seemed to stare past her at something on the wall.

‘Is there a dog here somewhere?’

Fry didn’t know what to say. She looked at Cooper to see how he was reacting, but he was quite still, watching carefully.

She paused to gather her thoughts before her next question. But Lowther wouldn’t allow a pause.

‘One of my neighbours has a dog. A cross-bred Alsatian. Long-haired, shaggy – you know? All the time I’ve lived in the apartment, I’ve never heard it bark. Not even when the binmen come in through the back gate.’

‘Why does that worry you, sir?’

‘How do you know what’s a dog, and what isn’t? Dogs are domesticated wolves. But wolves don’t bark. So if a dog doesn’t bark, is it actually a wolf? It’s a question of identity, you see.’

‘Mr Lowther, when did you last see your sister?’

‘Oh, Lindsay? Last week. It could have been the week before.’

‘Did you visit the house in Darwin Street on that occasion?’

He hesitated, contorting his mouth as if trying to work around some words that he couldn’t pronounce.

‘I can’t remember.’

‘Surely you can remember where you last saw your sister.’

Lowther stared at her. She noticed that the focus of his eyes was shifting back and forth, like someone trying to get a fix on a constantly moving object. Fry began to feel as though she wasn’t really there to him. Not all of the time, anyway.

‘I can’t remember. Did I say that already?’

Fry deliberately shifted her position, made a show of moving her notes on the table, gestured with her hands in front of her face. Anything to make sure she had John Lowther’s full attention.

‘I know you were very close to your sister, sir. But what sort of relationship do you have with your brother-in-law, Brian Mullen? Would you say there was some resentment between you?’

But Lowther barely seemed to have heard her. He made that chewing movement with his mouth again. Fry decided he wasn’t trying to pronounce the words, but to swallow them, to suck them back into his mouth before they reached the air.

Then, astonishingly, he smiled at her. It was a charming smile, friendly and guileless. What a niceconversation we’re having his expression seemed to say.

‘Is there another question?’

Fry sighed. ‘Yes. Mr Lowther, have you ever seen this before?’

She showed him a photograph of the wooden dinosaur.

‘Tyrannosaurus.’

‘Have you seen it before?’

‘No. Is it from abroad?’

‘We don’t know.’

‘Some people go abroad, hunting for whores. No, for babies.’

‘What?’

‘I’m sorry, I get confused sometimes. I’m not sure what you’re asking me. Is it time?’

Fry automatically looked at her watch. ‘Time?’

‘Time to leave.’

‘Do you want to leave, sir? You’re only here voluntarily, so you can leave whenever you want. We can’t keep you against your will. But we only want to ask you some questions, Mr Lowther. We’re trying to find out how your sister and her children died.’

‘What are they saying?’ said Lowther.

Again, he seemed to be looking at something behind her. Or perhaps not looking at something, but listening.

‘Are you all right, sir?’ she asked.

‘You don’t have to believe what people are saying, you know.’

‘I’m sorry, sir, I don’t quite follow –’

‘The things they say,’ he insisted. ‘They aren’t always right. You don’t have to believe them.’

‘Which people do you mean particularly?’

Lowther looked anxious. A bead of sweat formed at his temple and trickled slowly towards his jaw.

‘Whoever it is that you’re listening to. I don’t know who they are. I don’t know who any of them are.’

‘What have people been saying to you, sir? Have you been hearing rumours? Please share any information you have.’

Lowther tilted his head. ‘I’ve got exceptional hearing, I’m told. I can hear the people in the next room now.’

Fry tried for a while longer, probing for information about his feelings towards Brian Mullen, and about the last time he’d visited the Mullens’ house in Darwin Street. But she could feel that she was getting nowhere. The conversation seemed to veer off in directions that she had no control over, and she didn’t know how to bring it back under control. She just didn’t have anything of substance to use against Lowther and pin him down.

When the interview was finally over, they watched John Lowther leave. Then Fry walked back and checked Interview Room Two.

‘There wasn’t anyone in the next room,’ she said.

‘So what was he hearing?’ asked Cooper.

‘I don’t know.’

‘Something outside? Someone chatting in the corridor?’

‘Maybe.’

‘Some people do have particularly good hearing. They say blind people develop their other senses to compensate.’

‘So what is John Lowther compensating for?’ said Fry. ‘Let’s face it, he’s unbalanced.’

‘Hang on, Diane. He could be faking it.’

‘Faking it?’

‘Well, all that stuff was verbal. It was like a smokescreen. He didn’t actually answer any of your questions, as I’m sure you noticed.’

‘A bit of a teacake,’ said Fry thoughtfully.

‘What?’

‘It was something Gavin said.’

‘Well, we shouldn’t underestimate Gavin’s judgement.’

‘I think I’ll get John Lowther’s background looked into,’ said Fry. ‘Faking it, or not.’

Listening to the interview tapes afterwards, Cooper noticed a pattern to John Lowther’s answers. Sometimes he spoke quickly, the words spilling out with no prompting. At other times, he was hesitant, leaving long pauses before he answered. During these periods, he seemed to ramble and go off at tangents, often failing to address the question altogether.

At other times, Lowther seemed eager to anticipate what his interviewer was going to say, and tried to complete her sentences for her, often guessing the wrong word from its initial letter or sound. It sounded like a verbal equivalent to the predictive text function on his mobile phone. Both produced gibberish too often to be any real use.

Cooper had heard this kind of language before. The sound of it brought back so many unpleasant memories that he knew he was reacting on an emotional level. He tried to suppress the response, to smother assumptions that might prevent him from being objective. These days, his antennae twitched at the first sign of aberrant behaviour in those around him. Right now, he was even more touchy on the subject, thanks to Matt and his obsessions. But not every eccentricity or verbal quirk was a sign of mental illness.

He looked around for Fry. ‘I wonder if Lowther might have had experience of police interviews before,’ he said.