As the team gathered, Alex saw Berlin glide past in the corridor. She didn’t even deign to look at him, nor did she comment on the fact that they were using the Lions’ Den when she’d said only the previous day that it wasn’t to be used. Ross hadn’t been invited; they would update him later.

‘So where are we?’ he began. ‘Fredrika, could you tell us what you heard from London yesterday?’

Fredrika passed on the information Linda Sullivan had given her. Beata Benke’s husband had also been murdered, and they now knew that he’d taken Beata’s wedding ring after her death.

‘Do we seriously think he died as a result of a random burglary?’ Ivan asked when she’d finished.

Eager Ivan. He seemed a little less eager now, which made Alex feel sad.

‘No, we don’t. Or at least I don’t.’

‘Nor me,’ Fredrika said, which made Ivan’s face light up. ‘The murderer knew exactly what he was after. On the other hand, I’m not sure if the person who took the ring had intended to kill Beata’s husband, or if it became necessary in the heat of the moment, so to speak.’

Alex was trying to work out a timeline. ‘When did he die?’

‘In June.’

‘In June . . .’ An unpleasant thought was taking shape in Alex’s head; the murderer they were looking for had made his plans months in advance.

‘That still doesn’t explain why Lovisa Wahlberg also had to die,’ Ivan said.

He was absolutely right. Nor did they know whether there was a connection with Noah Johansson’s death – if it hadn’t been for the letter Alex had found. The letter that had kind of hidden itself behind the bookshelf.

Could the words used in that letter be dismissed as a coincidence?

He didn’t think so.

He thought it had been written by the murderer.

But what the hell was it doing in Noah’s office?

He cleared his throat, unsure of how to proceed.

‘Did you want to say something?’ Fredrika was looking at him. ‘I was going to talk about the book we found at Malcolm Benke’s house.’

Alex waved his hand in a gesture of agreement, and Fredrika went over what she’d found out from her husband, the professor. This was news to Alex.

‘So there are very few copies of this book around,’ she concluded.

‘Could it help us to find our perpetrator?’ Alex asked.

‘I doubt it, unfortunately.’

‘It might still be worth contacting antiquarian bookshops in the Stockholm area,’ Ivan suggested. ‘See if they’ve heard of the book, if anyone’s asked about it.’

Alex glanced at Fredrika.

‘Good idea,’ she said. Ivan made a note.

Alex took over. ‘The murder weapon – we must have more information by now.’

One of the CSIs sat up a little straighter. If she’d been a cat she’d have purred.