‘It’s unbelievable that Lianping would have done all that for the investigation.’

‘Don’t think she has done that for you, my husband. It’s for Inspector Chen. By the way, any news about his trip to Wuxi?’

‘No news, but one more question,’ Yu typed back. ‘If she had worn the mask to the food stall, what would she have done with it when she started eating?’

‘She could have put the mask in her pocket or purse.’

‘Was it possible to have the mask on by wearing only one strap around her ear?’

‘What’s the point of doing that? The mask would get smeared with the street food, or it could be blown away by the wind.’

‘Exactly, Peiqin,’ Yu typed back. ‘You are really the better half of a cop.’

‘Like in a favorite proverb of Old Hunter’s: “When she marries a cock, go along with the cock, and when a dog, with the dog.” Alas, I married a cop.’

There was no possibility of pulling pig-headed Detective Qin around, Detective Yu realized, even if he tried to talk to him again with the combined arguments of Peiqin and Inspector Chen. So Yu decided to move further along that direction by himself.

The first step was for him to find more information about the yellowish mask.

To his dismay, however, the Internet research failed to show any picture of a yellowish mask.

For his subsequent telephone inquiries, none of the pharmacy stores responded in a positive way either. Basically, they had never carried a yellowish mask. According to the salespersons, some young girls might have tried to make their masks prettier by adding flower or bird sticks, but a yellowish mask was not preferable by any standard.

Not willing to give up so easily, Yu went out to several pharmacies in person, carrying the pictures of the mask in question.

As anticipated, his police badge enabled him to get some more detailed information from the people working there, though far from close to anything like a breakthrough.

‘We have carried quite a variety of masks, Officer Yu. For instance, a pinkish one with embroidered patterns was quite a hit among young girls several months ago. People could not help taking another look at them. And the “another look” effect is what they really want. But for a yellowish mask, no, I don’t think so.’

‘Masks are the hottest commodity on the market of late, produced by quite a number of companies, and the most popular made by 3M. The American brand, you know. Some young people even wear them as a sort of personal or political expression, depending on the occasion. But we do not carry anything yellowish. No customer would care for such a color.’

It was not until the fourth store Yu visited that a medical supply clerk studied the pictures of the masks and shook his head dubiously.

‘I’m the buyer for the store, but I’ve never seen such a mask – except in a sci-fi movie, the name of which I forget. Some hospital may have specially ordered that, though. It looks like it’s pre-treated, immersed in anti-bacterial solution.’