Tony clicked on his e-mail in-box again. He’d been checking every fifteen minutes or so, trying to fool himself that he was pursuing the investigation. The truth was he wanted to hear from Carol. But still there was nothing from her. He wondered what she was doing. She’d said nothing about her plans for the day, other than that she was waiting to hear from Radecki about the arrangements for their Rotterdam trip. Oh well, at least Marijke had got back to him.

Hi, Tony

I have some very interesting news. No point in copying it to Petra, because she’s on surveillance today, and Carol is of course involved in her undercover. But I wanted to talk to you about this.

We have a speeding ticket issued to Wilhelm Albert Mann on the date of de Groot’s murder, just after nine in the evening. It was a camera that caught him, not a cop, and we have a photo of the car, a black Volkswagen Golf with Hamburg plates. Mann’s address is a boat. The Wilhelmina Rosen. I checked with someone in a shipping registry and this is a big Rhineship, they go all over Europe. What do you think? Is this worth checking out? I am reluctant to call the police in Köln, they will think it’s crazy. If you agree it is worth checking out, I have a list of possible places in and around Köln where a Rhineship could be waiting for the river to subside.

You can call me, I think.

She was right, he should call her, but first he needed to check something. He reached into his bag and pulled out the papers from Schloss Hochenstein. Of course, if Mann was their killer, it was possible that the person who had made him suffer didn’t share his surname. His maternal grandfather, for example, would probably be called something completely different. But if his luck was running, there might be an illuminating correlation in there somewhere.

He hastily looked down the alphabetized lists. It was a fairly common name, and he found eight children whose surname was Mann. Five he dismissed at once. They had been euthanased on the grounds of either mental or physical handicap. A sixth, Klaus, had died of pneumonia within a couple of weeks of being admitted to one of the feeder hospitals in Bavaria. Gretel, the seventh, had been admitted to Hohenschönhausen, but the records said nothing about her. The eighth name was the one that leapt out. Albert Mann, from Bamberg, had been taken to Schloss Hochenstein aged eight, diagnosed with chronic anti-social behaviour. The only comment under his treatment regime was Wasserraum.

Tony grabbed the phone and rang the number Marijke had given him. ‘Marijke?’

‘Ja?’

‘It’s Tony Hill here. I got your e-mail.’

‘You think it is something?’