‘Things have moved on a little,’ was all Rebus said, in reply to Devlin’s comment. He was drinking coffee from a local café; not up to his barista’s standards, but better than the stuff from the station’s vending machine. He’d had a broken night, waking up sweating and shaking in his living-room chair. Bad dreams and night sweats. Whatever any doctor could tell him, he knew his heart was okay – he could feel it pumping, doing its work.

Now, the coffee was just barely stopping him from yawning. The detective at the computer had finished the draft and was printing it out.

‘There’s something … something not quite right,’ Devlin said, not for the first time. Rebus took a look. It was a face, anonymous and forgettable. ‘It could almost be female,’ Devlin went on. ‘And I’m pretty sure he was not a she.’

‘How about this?’ the detective asked, clicking the mouse. Onscreen, the face developed a full, bushy beard.

‘Oh, but that’s absurd,’ Devlin complained.

‘DC Tibbet’s idea of humour, Professor,’ Rebus apologised.

‘I am doing my best, you know.’

‘We appreciate that, sir. Lose the beard, Tibbet.’

Tibbet lost the beard.

‘You’re sure it couldn’t have been David Costello?’ Rebus asked.

‘I know David. It wasn’t him.’

‘How well do you know him?’

Devlin blinked. ‘We spoke several times. Met one another on the stairs one day, and I asked him about the books he was carrying. Milton, Paradise Lost. We started a discussion.’

‘Fascinating, sir.’

‘It was, believe me. The laddie’s got a brain on him.’

Rebus was thoughtful. ‘Think he could kill someone, Professor?’

‘Kill someone? David?’ Devlin laughed. ‘I doubt he’d find it quite cerebral enough, Inspector.’ He paused. ‘Is he still a suspect?’

‘You know what it’s like with police work, Professor. The world’s guilty until proven otherwise.’

‘I thought it was the other way round: innocent until proven guilty.’

‘I think you’re confusing us with lawyers, sir. You say you didn’t really know Philippa?’

‘Again, we passed on the stairs. The difference between David and her is that she never seemed to want to stop.’

‘Bit stuck-up, was she?’

‘I don’t know that I would say that. She was, however, raised in a somewhat rarefied atmosphere, wouldn’t you think?’ He grew thoughtful. ‘I bank with Balfour’s, actually.’

‘Have you met her father then?’

Devlin’s eyes twinkled. ‘Good Lord, no. I’m hardly one of their more important clients.’

‘I meant to ask,’ Rebus said. ‘How’s your jigsaw coming along?’

‘Slowly. But then that’s the inherent pleasure of the thing, isn’t it?’

‘I’ve never been one for jigsaws.’

‘But you like your puzzles. I spoke to Sandy Gates last night, he was telling me all about you.’

‘That must have done BT’s profits a power of good.’

They shared a smile and got back to work.