Jäger paused, pursing his lips. ‘I can’t . . . directly. Let’s just say that in my line of work you come across information – information that should not, in any circumstances, be shared with the Kriminalpolizei. Some of it might just be harmless, or harmful, tittle tattle. But some of the information that passes through our hands can be very dangerous to the Republic.’

‘You’re not really making any sense.’ She began to turn away. ‘I’m not in the mood to be listening to riddles – especially from you. Remember what I know about you.’

Jäger’s face coloured a strange tinge of red, as though he was about to burst a few blood vessels. ‘I haven’t forgotten,’ he said, slowly, holding on to Müller’s arm. It was a light grip, but Müller had no doubt it would become fierce if she moved away any further. ‘But believe me, we have a shared interest in this. There are two things. One, this school director had certain links with our Concrete Man.’

‘Who you insist is Bodo Achterberg.’

Jäger nodded. ‘The dental records leave no doubt.’

Müller wondered if this was the time to tell Jäger what they knew – that those dental records had been faked. The trouble was, Jäger almost certainly knew that – no doubt the Ministry of State Security themselves had faked them. But why? The only way she was going to find out was by continuing to play along with the Stasi’s game, whatever it was, and see how things panned out. So she simply nodded.

‘And Achterberg and our latest victim had something in common.’

‘What?’

‘They both preferred the company of men.’

That didn’t seem to tie in with what everyone else had said about Bodo Achterberg: that his alcoholism was linked to being jilted at the altar by the female love of his life. Müller couldn’t help thinking this was another piece of disinformation. But she kept those thoughts to herself. ‘And?’ she asked.

‘And therefore, it’s perfectly legitimate for you to begin an inquiry into the death of Heinz Schenk, because of possible links to the death of Bodo Achterberg.’ Müller had only just learned of the TV tower jumper’s identity from his ID card. Why wasn’t she surprised that Jäger knew it already? ‘And in respect of any investigation into Schenk’s life, you should speak to this woman.’ He delved into his jacket pocket and produced a torn-off page from a pocket notebook.

Müller read the neat handwriting which she recognised as Jäger’s own. Frau Olga Voights, Room 1015, Kinder und Jugendsportschule Rosa-Luxemburg, Oberhof, Bezirk Suhl, DDR. ‘Is she a teacher there?’

‘No. She’s the head of the in-house cleaning and laundry service for the school.’

‘And what will she be able to tell me?’