‘How did it go?’ she asked briskly.

Fabel was about to answer when a uniformed SchuPo arrived to escort Klugmann to forensics. Klugmann’s and Maria’s eyes met for a moment; Klugmann’s eyes seemed blank, as if Maria weren’t there, while Maria frowned, as if trying to work something out.

‘You know him?’ asked Fabel when Klugmann and his escort were out of earshot.

‘I don’t know … I thought I recognised him, but I couldn’t say where I’ve seen him before …’

‘Well, it is possible. He is ex-Polizei Hamburg.’

Maria shrugged again, this time as if she were shaking off an irritating inconsequence. ‘How did you get on with him anyway?’

‘He’s obviously not our guy, but he’s dirty. Everything is just wrong about him. There’s something he’s not telling us. In fact, there’s a lot he’s not telling us. How did you get on?’

‘I talked to the manager of the Tanzbar, Arno Hoffknecht. He confirms that Klugmann was there working until after one-thirty.’

‘Could Hoffknecht be covering for him?’

‘Well, you have to see this guy to believe him. He is as sleazy as they come. Made my flesh crawl.’ Maria mimed a shudder. ‘But no, he’s not covering for him. Too many other people saw Klugmann throughout his shift. Davidwache KriPo have also checked out Klugmann’s claim that he went everywhere in the same taxi …’

‘He just told us the same story.’

‘Anyway, the driver confirms that he picked up Klugmann at the club at one-forty-five, took him to a Kneipe in the Hafen – Klugmann told him to wait – then he dropped him at the apartment about half past two.’

‘Okay. Anything else?’

‘Yes, I’m afraid there is,’ said Maria, and handed Fabel the print-out of the e-mail she had been holding in her hand.

Wednesday 4 June, 10.00 a.m. Polizeipräsidium, Hamburg.

Fabel read it out loud again, then put the page back down on the table and walked over to the window. The briefing room was on the third floor of the Polizeipräsidium. The traffic below pulsed with the changing of the traffic lights: the reassuring rhythm of Hamburg life.

‘And the e-mail was addressed to you, personally?’ asked Van Heiden.

‘Yes, the same as the last one,’ Fabel sipped at his tea. He kept his back to the others and looked out through the rain, across Winterhuder Stadtpark to where the city centre jutted into a steel grey sky.

‘Is there no way we can trace it?’ asked Van Heiden.

‘Unfortunately not, Herr Kriminaldirektor.’ It was Maria Klee who answered. ‘Our friend seems to have a pretty sophisticated understanding of information technology. Unless we actually catch him online, there’s no way we can locate him. Even then it would be unlikely.’

‘Have we had Technical Section look at this?’

‘Yes sir,’ said Maria Klee. Fabel still didn’t turn but kept focused on the pulsing traffic below. ‘We’ve also had an independent expert look at the e-mail. There’s just no way we can track it back.’