Tom Schiwy had the knack of earning affection and sympathy from those in his presence just by looking at them. Not a bad qualification for a liaison teacher, although when she was a girl Julia would never have disclosed to such a good-looking man that in PE the class sneered at her for being a roly-poly. These days her weight was still north of the German average, but the years had been good to her. The podgy teenager had turned into a round, but well-proportioned woman who’d learned not to get exasperated by her powerful upper arms and thighs, big bottom or chubby cheeks, but to accept the compliments that plenty of men gave her: for her eyes that sparkled with life, her pout and her dark, slightly curly hair that framed her oval face like an expensive painting when not tied up as it was now, emphasising her high forehead with the little beauty spot above her right eyebrow.

‘What now?’

A postcard-sized video window had opened up before Julia’s eyes.

‘What’s that?’

‘That… that…’ Tom stammered. ‘It’s hard to… Please just watch it.’

‘You’re really scaring me,’ she repeated, but tapped on the large arrow in the centre of the video file.

The recording that now began was typical of the quality of those hidden cameras familiar to reality TV shows, where amateur detectives try to catch out unfaithful husbands. A time code in the bottom corner of the screen revealed that the video had been taken five months earlier, in the spring of this year.

To begin with neither the lighting nor zoom were right, assuming that the gadget responsible for these shaky pictures had such a function. It took a while for Julia to see that someone was filming from a moving car. It was dark, and drizzle was falling onto the windscreen, which was why the tail lights of the car in front blurred the picture for the viewer. The camera panned across a black dashboard to the passenger seat and captured the front of a sombre tenement block, a grey concrete eyesore of the sort you see on every second corner in old West Berlin.

‘Why do I need to watch this?’ Julia asked as the car slowed down and now passed at walking pace by the forecourt of a second-hand car dealer.

‘Because of this,’ Tom replied at the moment when the car stopped at a driveway and the electric window on the passenger side disappeared into the door.