‘This isn’t gratuitous prying, Baarda, it’s a comparable study. Work with me. Somewhere deep inside, you must fantasise about you and your wife being reconciled. For that to happen, the affair would have to end. You’ve imagined it. What goes through your head in those small, dark hours when people screw and cry and imagine killing their abusive partner, or suddenly decide to embezzle money from their company?’

Baarda was silent. He sat down on the edge of Connie’s bed and leaned back on his elbows.

‘It’s about time,’ he said. ‘Enough months go by that the affair becomes dull. It’s not exciting any more. They grow bored of one another. Their relationship becomes as much a routine as our marriage, and she sees that she’s just swapped one thing for another.’

Connie pressed a hand against her stomach.

‘Brodie,’ she said softly. ‘I knew you had the answer. That’s what he doesn’t have. He’s out of time. It explains the decreasing periods between each offence. He’s taking more risks because he has less opportunity to reorganise. There’s no scope for repairing the relationship he’s imagined with Elspeth. He’s under pressure, unlike you. You feel no urgency because giving your wife time allows you to ignore the reality of the situation.’

‘Which is?’

‘That your relationship is dead. You don’t feel anything for her any more.’

‘Bullshit,’ he said.

‘Really? When did you last imagine your wife naked and get hard in the middle of the day?’

‘Are you saying that’s what happens to our murderer when he thinks about Elspeth?’

‘I’m saying he’s running out of time, and we need to figure out why. That’s the key.’

Connie closed her eyes and saw the image of the man every police officer in a hundred-mile radius was hunting right now, so gaunt he was almost the physical embodiment of the ghoul the public believed him to be. She stopped breathing. Her heart hammered wildly out of rhythm in her chest. She gasped.

‘What’s wrong?’ Baarda asked, crossing the room in two short strides and taking hold of her upper arms. ‘Connie?’

‘He’s not just physically ill,’ she said. ‘If that was why he’s so thin, he’d still be conscious of consequences. He could still be arrested and imprisoned. Maybe he’s not dead enough for our liking, but he might not agree. If he was more than just unwell – in his own mind at least – it would explain the risk-taking, the urgency … everything.’

‘What are you talking about?’

She lurched for her desk and grabbed her laptop.