Fry stood up, abandoning her untouched coffee on a corner of the DI’s desk. No matter how hot it seemed at first, coffee from the machine always turned cold and undrinkable with unnatural speed.

‘But the case against him for Rose Shepherd will be tight enough, won’t it?’

‘If forensics come through,’ said Hitchens. ‘With luck, we’ll get a DNA match from the car, gunshot residue from his clothes, footwear impressions from the track where the Shogun was abandoned. There’ll be something, don’t worry. We’ll build a tight enough case. In fact, it’ll be a headline grabber when it comes to trial.’

Fry still hesitated. ‘I wouldn’t want the Mullens to get forgotten in all the excitement. In a way, the arson was a far worse crime.’

The DI nodded. ‘They won’t get forgotten, Diane, I promise you. Why don’t you get on with that line of enquiry now, and start sifting out some possibles from intelligence? The IU ought to be able to suggest a few names you’d go to if you wanted a nice house fire in a hurry.’

There was one other subject they weren’t mentioning. It had all been gone through already, and no doubt it would be thrashed out again before long.

‘And the Lowthers?’

‘They’re coming in tomorrow,’ said Hitchens. ‘And I’m not looking forward to it one bit.’

‘Ben Cooper has gone home, by the way,’ said Fry, though the DI hadn’t asked her.

Hitchens looked hurt, as if she’d accused him of not caring about his officers. ‘Yes, I know. But he seemed OK, don’t you think?’

‘As far as I could tell. He gave a clear enough statement, but that’s just training. It was a hell of a thing to happen. Ben was right there, and he did his best. John Lowther was always going to do it, one way or another.’

‘But knowing Ben . . .’ said Hitchens.

‘He’ll be blaming himself. Right.’

At home that night, Cooper was going automatically through his routine – feeding the cat, taking a shower, checking the fridge, remembering he had no food in the flat. That was the great thing about routines – you didn’t need to think. You could switch off the brain and freewheel.

Then he switched on his PC and opened Outlook. The evening’s crop of email included a series of George W. Bush jokes, sent by his friend Rakki from his office address. It looked as though he’d forwarded them to everyone he knew, so the jokes would be doing the rounds for a while yet. In fact, Cooper was sure he’d seen most of them already.