‘MacSwain means “Son of Sven”.’

‘I knew it!’ Werner said. ‘And so did Anna. There was something didn’t gel with MacSwain.’

‘I’ve just had a chat with Norbert Eitel,’ continued Fabel, ‘who is still in custody downstairs. I told him that I knew all about Vitrenko and MacSwain’s part in the rapes. He didn’t answer me, mainly because his lawyer told him not to, but the look on his face said it all. The look of a man who has got in too deep. MacSwain’s our man all right.’ Fabel turned to Maria. ‘We still have that team on him?’

‘I’ve sent an extra officer over, but the surveillance guy who’s been watching MacSwain says he hasn’t moved all evening.’

‘Okay,’ said Fabel, ‘I want everyone ready to roll in twenty minutes. Maria, tell the surveillance team to stand by.’

A uniformed policewoman knocked and stuck her head around the conference room door.

‘There’s someone in reception to see you, Herr Haupt-kommissar. A Frau Kraus …’

Margarethe Kraus could have been any age between forty-five and sixty-five. She was one of those women for whom the compensation of having looked middle-aged in youth was that she would probably still look middle-aged when she was in her late seventies. Whatever family resemblance there had been between mother and son must have been erased from Hansi’s features by his years of drug abuse. Frau Kraus had a round, empty face and smallish brown eyes that wore a look of immeasurable weariness, as if she had never left a moment of her life behind her, instead carrying it with her everywhere she went.

She was sitting in the reception waiting room, by the window, which gleamed obsidian against the night outside. Her small hands were folded over a small envelope. She stood up awkwardly when Fabel came in.

‘Frau Kraus?’ Fabel smiled and extended his hand. ‘I’m so sorry about your loss.’

Margarethe Kraus smiled bitterly. ‘I lost Hansi many years ago. The difference is now we have a body to grieve.’

Fabel found he had no words. He nodded with a careful balance of sympathy and understanding. After a silence that seemed longer than it was, Fabel said:

‘You wanted to see me, Frau Kraus. Was it about Hansi?’

The eternally middle-aged woman did not speak, but handed Fabel the envelope. Fabel made a confused expression.

‘It’s from Hansi,’ she said.

Fabel opened the envelope. The letter had been written in pencil, but remarkably neatly. It was as if some distant memory of schoolroom discipline had invested itself into the writing. For Hansi, this had obviously been an important letter. It made painful reading. The majority of the letter was of a highly personal nature: basically, Hansi was apologising to his mother for the worry and distress he had caused her and his sisters. Fabel had begun to wonder why Frau Kraus had chosen to share this intimacy with him when he reached the closing paragraphs.

The reason I write now, Mutti, after so many years, is because I think my troubles are over. I don’t want you to be sad or frightened, but I have to tell you that I think someone may be coming after me. If I am right, then I don’t think we’ll ever see each other again. If something bad happens to me, I want you to take this letter to Kriminalhauptkommissar Jan Fabel at the police Präsidium. He is an honest policeman, I think, and he will be able to get the people who have done whatever it is they have done with me.