He hadn’t drawn the curtains and Perez looked out into the darkness. There were the lights of a ship, a big tanker from the shape of it, moving steadily south. Maurice had turned his body away, as if to make clear that the discussion was over. It was time for Perez to leave.

‘We’ve traced Angela’s mother.’

No reaction.

‘She’s coming into Fair Isle tomorrow. I’ve booked her on to the afternoon plane.’ He paused, but still Maurice gave no sign that he’d even heard. ‘I think she’d like to meet you, but that’s your decision.’

At last Maurice turned his head. ‘Of course I’ll meet her. You’ll make the arrangements, will you, Jimmy? You’ll bring her here.’

‘Why had Angela booked train tickets to go from Aberdeen to London at the beginning of November? It seems she had a meeting with her publisher, but do you know what that was about?’

‘No! It seems to me now that I didn’t know anything about her. She was my wife, but she could have been a stranger.’

He looked up at Perez, now obviously expecting him to leave, but still Perez sat where he was.

‘Is the lighthouse tower always kept unlocked?’

‘Of course not, Jimmy. It’d be a health and safety nightmare. We have kiddies staying here in the summer. You couldn’t have them running up and down the stairs, tampering with the light.’

‘But I found it unlocked this afternoon.’

Maurice shrugged. ‘Is it important?’

‘It could be. Did you have a key here?’

There was a pause. Maurice looked up from his whisky. ‘It was kept with the big bunch on the hook in the larder.’

‘The same one as the key to the bird room?’

‘Yes, but we never used most of them.’

‘But anyone staying in the centre would know where they were kept?’

‘Only if they’d asked Jane. She was the keeper of the keys.’ Then Perez thought at last he’d found a motive for the cook’s murder. She’d known the killer had been in the tower. Had he hidden something else there?

They sat for a moment in silence. ‘Were you never tempted to go up there?’ Perez asked at last. ‘To see where Angela was going, to see who she was with? You’d get a view from there of everything that was going on.’

Maurice set down the glass so violently that some of the liquid spilt on to the polished table. ‘You don’t get it, do you, Jimmy? I didn’t want to know where she was going or who she was meeting. As long as she came home to me every evening I didn’t care.’