‘He’s a free agent,’ she said.

‘But you were worried last week.’

‘Was I?’

‘When you closed the door on me. I’ve seen the look enough times to know.’

She folded her arms. ‘So?’

‘So one of two things, Briony. Either Jake’s in hiding because he’s in fear of his life.’

‘Or?’

‘Or he’s already dead. Either way, you can help.’

She swallowed. ‘Mitch …’

‘Did Jake tell you why Mitch was killed?’

She shook her head. Rebus tried not to smile: so Jake had been in touch since they’d last spoken.

‘He’s alive, isn’t he?’

She bit her lip, then nodded.

‘I’d like to talk to him. I think I can get him out of this mess.’

She tried to gauge the truth of this, but Rebus’s face was a mask. ‘Is he in trouble?’ she asked.

‘Yes, but not with us.’

She looked back at the pool, saw everything was under control. ‘I’ll take you,’ she said.

They drove back through the moorland and down past Lerwick, heading for a place called Sandwick on the eastern side of Mainland, just ten miles north of where their helicopter had originally landed.

Briony didn’t want to talk during the drive, and Rebus guessed she didn’t know much anyway. Sandwick turned out to be a spread of land taking in older settlements and oil-era housing. She directed them to Leebotten, a nestling of sea-front cottages.

‘Is this where he is?’ Rebus asked as they got out of the car. She shook her head and pointed out to sea. There was an island out there, no sign of habitation. Cliffs and rocky approaches. Rebus looked to Briony.

‘Mousa,’ she said.

‘How do we get there?’

‘Boat, always supposing somebody’s willing to take us.’ She knocked on a cottage door. It was opened by a middle-aged woman.

‘Briony,’ the woman said simply, more statement of fact than greeting.

‘Hello, Mrs Munroe. Is Scott in?’

‘He is.’ The door opened a little wider. ‘Come in, won’t you?’

They entered one decent-sized room which seemed kitchen and living room both. A large wooden table took up most of the space. By the fireplace were two armchairs. A man was rising from one of them, unhooking wire reading-glasses from his ears. He folded them and put them in his waistcoat pocket. The book he’d been reading lay open on the floor: it was a family-sized Bible, black leather cover and brass clasps.

‘Well now, Briony,’ the man said. He was middle-aged or a little after, but his weatherbeaten face was that of an old man. His hair was silver, cut short with the careful simplicity of a home barber. His wife had gone to the sink to fill the kettle.

‘No thanks, Mrs Munroe,’ Briony said, before turning back to the man. ‘Have you seen Jake lately, Scott?’

‘I was over there a couple of days back, he seemed fine.’

‘Could you take us across?’

Scott Munroe looked to Rebus, who stuck out a hand.

‘Detective Inspector Rebus, Mr Munroe. This is DI Morton.’