‘This is going back twenty-odd years, mind, but it might explain the grudge.’

Rebus thought for a moment. He knew why Clarke sought him out like this sometimes: she needed both a sounding board for her own theories and someone who might spot what had so far been missed. But then other times, she produced a perfect nugget herself, a nugget such as Elizabeth Mackenzie. ‘How’s DCI Trask shaping up?’ he asked, filling the silence while his synapses got to work.

‘I’ve no complaints so far.’

‘You mean she’s not being unduly swayed by Malcolm Fox?’

‘Something like that, despite him clinging to her like a limpet. Oh, nice work there, by the way.’

‘What?’

‘Fox’s notebook – the cock and balls you doodled on it while seated at his desk. He thinks it was one of us, and telling him the truth would mean admitting we allowed you the freedom of MIT.’

‘Simple pleasures, Siobhan. Has anyone listened to the 999 call?’

‘Woman’s voice, pretty shaken. Didn’t give a name when asked. Just described what she’d seen and added the address, rang off straight after.’

‘But there’s a log of the number she rang from?’

‘We’ve tried. No answer, but it’s a man’s voice asking the caller to leave a message. We’ll get a name and address eventually, but it takes time.’

‘So far it all sounds textbook, Siobhan. I suppose the widow will have to be questioned again. Far as we know, her and her sister were the last people to see him.’

‘Caller wasn’t a voice I recognised, if that’s what you’re asking.’

Rebus nodded. ‘Are the media behaving themselves?’

‘Just about. Though online is a pain. There was a press conference this afternoon. The DCI did fine.’

‘When do you start pulling in Haggard’s fellow officers?’

‘Probably tomorrow. I’m assuming you’ll warn your pal Fleck?’

‘He’s bound to know what’s coming.’

‘It’s not going to go away, John. Whatever stories Haggard was planning to tell at his trial, they’ll come out one way or another.’

‘Things don’t always, you know. People have gone to their graves taking their secrets with them.’ He stooped and fastened Brillo’s lead. ‘Fancy coming back for some tea?’

She shook her head, stuffing her hands into her coat pockets. ‘I should get back to the office. Might manage another couple of hours.’ She locked her eyes onto his. ‘Are you ready to face whatever’s coming, John?’

‘I’m like Billy Joel, Siobhan – an innocent man.’

‘Haggard seemed to imply that plenty of those had been put in prison on his watch.’

‘His watch, Siobhan, not mine. You parked outside the flat?’

‘More or less.’

‘Walk back with us, then. Here, you can take charge of Brillo.’

‘What for?’

‘It’s what detectives do, isn’t it? Follow leads?’