‘Great job,’ Chen said, raising his voice. ‘It’s definitely in the right direction, Detective Yu.’

‘So you also think it’s the signature, just like the torn mandarin dress in the other serial murder case. The criminal left or planted it there on purpose. A message possibly, not understandable to others, but understandable to himself.’

‘You’re correct. A message not yet understandable to others, but it will be. It’s a breakthrough. No question about it.’ Chen went on after a short pause, ‘Now I have studied the pictures. The mask … hold on, something else really strange about the mask, Yu.’

‘What about it, Chief?’

‘It is reminding me of a scene – something I saw just this morning – I was out for some street food …’

Yu knew better than to push, waiting patiently for Chen to go on.

So it was Chen’s turn to give a detailed description about the street scene that morning, particularly of the sesame-strewn earthen oven cake for the young girl with her mask off. He had paid extra attention to the scene without knowing why. It was because of something in the information concerning the crime scene of Xiang’s death, something raising a question in his subconscious mind, Chen now realized.

‘It’s also about the point you have raised regarding the mask. What was Xiang having for breakfast that morning? The earthen oven cake with the fried dough stick. For such a breakfast, people have to have it fresh and hot. Once cold, the taste would be mostly gone. Most people would start eating on the street. But how could someone have done so without taking off the mask?

‘And the scene of the cake-eating girl, in retrospect, really illustrates the point. She had a mask on while waiting in front of me in the line, but once she started eating, she took the mask off. Even so, it could be a bit messy to have the sesame-strewn cake on the street, with the sesame stuck to her lips and cheeks; she had to wipe her face with a pink paper napkin.’

Chen seemed to be talking in a rather jumpy way, but Yu got his point.

With the phone still in his hand, Inspector Chen moved into the Shanghai Writers’ Association, but he learned nothing new about Qiang there.

He remained in mysterious disappearance.

People were worried, but they were unable to do anything other than report it to the police bureau. And according to regulations, it was too early for the bureau to step in for an investigation. They had to wait at least another day.

So Chen had to make phone calls to someone surnamed Liao in the bureau, making sure that Qiang’s name was immediately put on the missing persons’ list.

‘He could be drinking a cup of tea somewhere, you know,’ Liao said darkly, ‘for a man with sensitive information in his position.’

That was exactly what worried Chen, but he said nothing about it to Liao, nor to the people in the association.