‘If Brian Mullen is thinking straight, he ought to realize the risk,’ said Cooper.

Fry shook her head. ‘This case has been the same all the way round. No one has behaved in a rational way. Everyone involved seems to have gone headlong towards their fate with blinkers on. You’d think they were a lot of lemmings throwing themselves off a cliff.’

‘Emotions,’ said Cooper. ‘Emotions always interfere with rational behaviour.’

Fry began to put together her notes to update the DI and Mr Kessen.

‘Do you want someone to check on the Heights of Abraham later, Diane?’ asked Cooper. ‘The Lowthers said that’s where John is likely to go.’

‘Yes, thanks.’

As she was on her way out of the room, Cooper remembered one more thing. ‘By the way, I’ve asked Dr Sinclair to listen to the interview we did with John Lowther. He’ll be coming in any time now.’

‘Good idea. It’ll be interesting to hear what he has to say.’

‘Would you be worried if you had hallucinations, Diane?’

Fry frowned. ‘I suppose so.’

‘Apparently a lot of people aren’t troubled by them and don’t seek psychiatric help.’

‘Really?’

‘Yes. It’s strange, isn’t it?’

Cooper felt he was putting it mildly. Of course, he only had his experience with his mother to go by. She’d certainly been troubled by the hallucinations caused by her schizophrenia, and so had everyone else around her. But his experience might be a narrow one.

‘What sort of hallucinations are we talking about, though?’ said Fry.

‘According to Dr Sinclair, the misattribution of internal events to an external source.’

Fry laughed. ‘Oh, those sort.’

After she’d been interrogated for twenty minutes by Hitchens and Kessen, Fry felt exhausted. Her eyes were dry and her skin felt grimy. She nipped down the corridor to the ladies’, where she splashed cold water on her face and practised controlled breathing for a while until she felt calmer.

Then she looked at herself in the mirror over the washbasin. Some days, it wasn’t a good idea to do that too often. If she wasn’t careful, she could suddenly get a glimpse of a person she’d almost forgotten – the girl who’d lived in those foster homes back in the Black Country. Sometimes it seemed like a million years ago. But at other times, she knew it was really just yesterday.

Fry had once seen a newspaper article that began: ‘Kate Adie, Marilyn Monroe, Jim Bowen, Larry Grayson, Edgar Allan Poe, Bill Clinton and Steve Jobs . . . What do they all have in common?’