‘This is more than an investigation, Alex. This is a drama. We have a murderer who doesn’t want to be misunderstood, but also doesn’t want to be stopped. That’s why the ring was on Malcolm’s finger – so that we’d know where to look. If it hadn’t been for the ring, we’d have spent a huge amount of time trying to find a client or business partner with whom Malcolm had had some kind of dispute. Or someone else who might have been angry enough to put a bullet in his chest.’

Her words found their mark, and the realisation they brought made Alex’s heart sink.

A murderer who doesn’t want to be misunderstood.

A murderer on a mission?

In which case how many more victims will there be?

He broke out in a cold sweat, then pulled himself together.

‘I’m wondering why the first letter arrived when Malcolm Benke was already dead, and the investigation was already under way, rather than at the scene of the crime, like the second letter.’

Fredrika focused on her food, stabbing at the strips of chicken as if she was trying to kill the bird all over again.

‘I said yesterday that we ought to go back to Benke’s place. I’m still convinced that I’ve seen the phrase “putting everything right” somewhere else. Maybe that’s why the letter was sent, because we’d missed a clue that was left in the house. And so the killer decided to be less subtle the next time, and pinned his message on the notice board.’

Alex’s phone rang.

‘Yes?’ he snapped.

‘Hello? Alex?’

It took a second for him to recognise Linda Sullivan’s voice.

‘Yes, hi,’ he said in English.

‘I just wanted to let you know that I’ve looked into what might have happened to Beata Benke’s wedding ring,’ she said, making no attempt to hide her excitement. Fredrika noticed the change in Alex’s expression, and put down her fork.

‘She wasn’t wearing it when she died,’ Linda went on. ‘There was a clear mark on her finger where it had been – you know how the skin is paler if you always wear a ring. It didn’t register with us at the time, nobody thought it was strange, but now you’ve told us it was on her father’s little finger, it’s interesting to speculate on where it’s been for all these years. Who took it.’

‘Absolutely,’ Alex said. ‘Absolutely.’

He’d known from the start that the ring was important, known that it told them something about the perpetrator.

‘Just an idea – what’s Beata’s husband doing these days?’

‘You think he could have murdered his father-in-law too?’ Linda said dubiously.

‘I don’t think anything, I’d just like to rule him out.’