Inspector Kwok.
Inspector Zhang knelt down carefully and peered under the bed. Another cockroach scuttled away and disappeared under the skirting board.
"We looked everywhere," said Inspector Kwok.
"I'm sure you did," said Inspector Zhang.
"But as you can see, it is a small apartment and there are no hiding places."
Inspector Zhang tapped the floor with his foot. . The bedroom floor was tiled, as was the sitting room, bathroom and kitchen. It was the same pale green tiles in all the rooms.
"How long were the men in the apartment?" he asked.
"Two minutes. Three at most. They left the boxes and then they took the trolleys back to the van."
Inspector Zhang nodded thoughtfully. He looked up at the ceiling. It was plaster, painted white.
He went over to the bedroom window and opened it. He peered out. Down below was a car park. There were no ledges or balconies, and no external pipework that would have allowed someone to have climbed out.
"We had a car down there with two undercover police officers," said Inspector Kwok. "They had the rear of the building under constant surveillance."
Inspector Zhang craned his neck to look upwards.
"If anyone had lowered the drugs up or down through the window, we would have seen it," Inspector Kwok said.
"One would hope so," said Inspector Zhang.
He pulled his head back in and looked over at Sergeant Lee., who was standing at the bedroom door, taking notes. "What do you think, Sergeant?"
Sergeant Lee looked up from her notebook. "It is a mystery, Inspector Zhang," she said.
"Indeed it is. Do you have any thoughts on how we might solve it?"
She frowned thoughtfully. "The drugs were brought into the apartment and they are clearly not here now," she said. "They must therefore have been removed. The question is how were they removed? If they were not lowered out through the bedroom window, then perhaps through the sitting room. There is a balcony there."
Inspector Zhang went through to the sitting room and opened the sliding glass door that led to a small balcony where there was an air-conditioning unit and three large ceramic plant pots which were filled with soil and the remains of long-dead flowers.
"We had the front of the building under observation, obviously," said Inspector Kwok. "During the time we had the building under surveillance no one appeared on the balcony."
Inspector Zhang examined the plant pots. They were each over two feet high with paintings of feeding cranes and bamboo on the side. They were of poor quality and the glaze was cracking.
Inspector Zhang tipped one of the plant pots on its side, then up-ended it and with a grunt lifted it up. Soil spilled out over the balcony.
He did the same with the other two plant pots. They both contained nothing but soil. Inspector Zhang stared down at the dirt thoughtfully. "So, the drugs are not on the balcony and they did not leave by the windows." he said quietly. "There are therefore only two possibilities. Either they are still in the apartment but so well hidden that we cannot see them, or they were removed by some other route."
"But how is that possible?" asked Inspector Kwok. "We have searched everywhere."
Inspector Zhang walked through to the kitchen. There was a broom leaning behind the door and he picked it up. He turned it upside down and methodically tapped the handle against each of the tiles on the floor. They all made a dull thudding sound as he hit them. He did the same in the shower room, and then repeated the process in the sitting room and the bedroom. Every tile sounded the same.
"Inspector Zhang, we checked the floor," said Inspector Kwok. "And the ceiling. Both are completely solid."
"I'm sure you did," said Inspector Zhang. "But there is no harm in my checking for myself."
He walked around the apartment, tapping the ceiling at regular intervals. He checked the kitchen, the shower room, the sitting room and the bedroom. There was no difference in sound anywhere, no indication that