‘But here’s another clue,’ Qin responded, raising his voice a little. ‘The video cameras at the Wenhui building entrance and exit happened to be down that night. In case of its being not an accident, Zhou certainly knew how to handle that as an insider, and for a reason known to him alone. According to his testimony, he left the office around twelve, but with the cameras down, that was not verified. He could have stayed on somewhere inside the building, in view of Xiang walking out, and followed her out to the stall for the fatal blow. He did not have to wait that long outside, standing or strolling about inconspicuously on the street.’

‘But I did not know anything about the camera problem at the Wenhui building, Detective Qin.’

‘Sorry, we too have just learned it.’

Yu did not think that was true. Qin had been reluctant to work with the Special Case squad, or to share the information with him.

‘And another question related to the scenario,’ Yu went on after a short pause. ‘How could Zhou have possibly obtained the video tape at the club?’

‘The earlier relationship between Xiang and Geng was no news to the people in the newspaper. Zhou was certainly in a position to have heard about it.’

‘But the video was made in the days when she still worked as a massage girl. Zhou came to know her after she started working as a journalist for Wenhui. How could that have been possible?’

‘At the time, the video was possibly made against Geng.’

‘Zhou had no grudge against Geng, had he? I think we have talked about it. No point going over it again. Even if it were the case, it should have been released at the time, with Geng still married to his former wife, and in the position of the vice mayor. So his affair with such a massage girl would have easily made the Weixin headline.’

‘I think you have made this point before, Detective Yu.’

‘And with her recent death, and his being in hospital, some people reacted to the tragedy not without a touch of sympathy.’

‘Yes, possibly less damage. But Geng’s known as a ruthless man, having crushed his opponents like ants, so one of them could have chosen to have the video come out in a different light. The combination of her death in a sensational murder and his exposure in a salacious massage scene. That could have called so much more public attention and devastated Geng in an irrecoverable way – at least from the revenger’s perspective.’

‘But the question remains: how could an ordinary journalist like Zhou have got hold of such a video?’

‘Internal Security has looked into that. Some club people secretly made videos like that for selling – for a really high price. It might be used for some secret purpose you may never imagine.’

‘Another question for your scenario: what about the other victims? They had done nothing against Zhou. In fact, they might not have known him at all.’