David’s mother, Theresa, was something else again. Her background could at best be called lower middle class, mother a nurse, father a teacher. Theresa had gone to art school but dropped out and got a job instead, providing for the family when her mother got cancer and her father fell apart. She worked behind the counter in a department store, then moved to window-dressing, and from there to interior design – for shops at first, and then for wealthy individuals. Which was how she met Thomas Costello. By the time they married, both her parents were dead. Theresa probably didn’t need to work, but she worked anyway, building up her one-woman company until it had grown into a business with a turnover in the low millions and a workforce of five, not including herself. There were overseas clients, and the list was still growing. She was fifty-one now, and showing no signs of slacking, while her husband, a year her junior, remained the man about town. Press clippings from the Irish news showed him at racing events, garden parties and the like. In none of the photos did he appear with Theresa. Separate rooms in their Edinburgh hotel … As their son said, it was hardly a crime.

David had been late going to university, having taken a year out to travel the world. He was now in the third year of his MA degree in English Language and Literature. Rebus remembered the books in his living room: Milton, Wordsworth, Hardy …

‘Enjoying the view, John?’

Rebus opened his eyes. ‘Deep in thought, George.’

‘You weren’t dropping off, then?’

Rebus glared at him. ‘Far from it.’

As Hi-Ho Silvers moved away, Siobhan came and rested against the side of Rebus’s desk.

‘So how deep in thought were you?’

‘I was wondering if Rabbie Burns could have murdered one of his lovers.’ She just stared at him. ‘Or whether someone who reads poetry could.’

‘Don’t see why not. Didn’t some death-camp commander listen to Mozart of an evening?’

‘Now there’s a cheery thought.’

‘Always here to make your day that little bit brighter. Now what about doing me a favour?’

‘How can I refuse?’

She handed him a sheet of paper. ‘Tell me what you think that means.’

Subj: Hellbank
Date: 5/9
From: [email protected]
To: [email protected]

Did you survive Hellbank? Time running out. Stricture awaits your call.
QuiM

Rebus looked up at her. ‘Going to give me a clue?’

She took back the sheet of paper. ‘It’s an e-mail printout. Philippa had a couple of dozen messages waiting for her, dating back to the day she went missing. All of them except this one are addressed to her other name.’

‘Her other name?’

‘ISPs—’ she paused – ‘Internet service providers will usually allow you a range of log-on names, as many as five or six.’

‘Why?’