It took them some time to open the access to the ventilation shaft. The ceiling looked as if it had been cast in one piece. The trapdoor fitted almost seamlessly into the brickwork. It also turned out, that the door was  marked incorrectly. The only clue as to which direction it was to be located, was provided by the fan in one corner. Starting from there, they tapped the ceiling and looked for thin cracks hidden under the plastering. 

Once they had found a crack, Xiao Dao used a sharp tool. Shortly afterwards, the panel detached from the ceiling and allowed them to climb up. A cool wind blew into the room through the opening. Wenjie discovered a large fan, just a few meters away from the entry point. Its blades spun and kicked up dust, which promptly got up his nose. He pressed the crook of his arm in front of his mouth in time. His sneeze was barely audible. 

The air shaft was slightly wider, which allowed him to turn around easily. Then, he helped Xiao Dao up. They followed the plan of the ventilation shafts to the next trapdoor. Below, Wenjie saw a corridor, which ended at a vault door. The corridor was not equipped with a safety net, but he discovered elevations on the floor and numerous holes in the side walls. 

Wenjie skillfully climbed over the opening, so that Ding Wei could also take a look down. 

“The traps go all the way to the door,” Ding Wei muttered. “I'm not sure if it's a good idea to throw something down and test where we can step.” He carefully reached one hand through the opening and touched the ceiling wall in the hallway. “Mmm ... this has a non-stick coating. Our shoes won't work there.”

Wenjie thought about it. “Will our ropes be enough, if we block the fan and tie it to it? Then we could rappel down and pick the lock without touching the floor.” At first glance, the lock on the vault door didn't look like it could be picked by one person. They both had to do it.

“Perhaps. Let's give it a try.” Ding Wei crawled back the way he came.

Wenjie waited and listened to the sounds he made. It wasn't long before he heard a rattling, hissing and crunching. The draught disappeared. Even the whirring of the fan could no longer be heard. 

Ding Wei returned. He had already put on a harness to which the rope was attached. 

Wenjie watched as he swayed slightly back and forth. Then, Xiao Dao caught hold of the edge of the vault door and gave him a signal. Wenjie quickly climbed back to the disused fan and attached his rope to it. Back at the trapdoor, he did the same as his friend and rappel down. 

In the meantime, Ding Wei had discovered, that the vault door did not have a non-stick coating. This allowed them to find extra grip with their feet on the edges of the metal door. 

“Let's get going.” Xiao Dao gave him a signal, whereupon Wenjie assisted him in picking the lock at the same time. The locking mechanism was not particularly complicated. It only took half a minute for the door to open. 

Ding Wei reached out a raised hand towards him. Wenjie pushed in. That was done. “Go back up and just let me down the rope. If something goes wrong and someone shows up here, they'll only catch one of us.”

Xiao Dao frowned. He didn't seem to like that. 

Wenjie patted him on the shoulder and nodded to him. He still believed, that this was just a simulation. Even if someone came, it was part of the plan. Of course, they still shouldn't get caught. If they successfully completed this mission, a return to Qingcheng would be within reach. Xu Zhengqing would not let the artifacts slip away. He reckoned, that the police would make sure they were displayed as bait in the museums. 

“Okay. Take care.” Ding Wei climbed back up the rope.

Wenjie waited, until he was at the top and lowered the backpack. It was now dangling just above the floor, half a meter from the door. Easy to reach without having to go out into the corridor. 

Xiao Dao gave him a hand signal from above, whereupon Wenjie held on to the top edge of the safe door. He then pushed his feet off the door and swung himself into the room. He landed on the floor light-footedly. 

The rope stretched and pulled him a little towards the door. Wenjie quickly held on to the frame. With his free hand, he released the rope, which then swung backwards. 

It was dark in the vault. But the light from the smartwatch helped him to find the light switch. Fortunately, the corridor in front of the room did not end at a window. Instead, it bent in front of a tall wall mirror. 

Wenjie's gaze wandered through the vault. In the center was a glass display case with archaeological finds. Paintings from different eras and cultures hung on the walls. Only a fraction of the treasures in the room could be attributed to China. There were no traps in here. 

Wenjie discovered small cameras in the corners of the walls. Damn. His hand found the light switch. Darkness flooded the room again. He glanced back into the hallway. Everything remained quiet. He found no evidence of a silent alarm either.  

He breathed a sigh of relief before moving along the wall. The smartwatch provided him with valuable assistance. Finally, he reached the paintings in question. They were hanging on ordinary brackets. He used the light from the smartwatch to take a closer look at the painting and its surroundings. There were no signs of a secret alarm. 

He took a deep breath. Then, he carefully lifted the painting from its mount. At the same moment, he heard a soft click. He wheeled around. His gaze caught the vault door, which was slowly closing. Wenjie hung the painting back on the holder and sprinted to the door. 

Before his eyes, the gap became narrower and narrower. Mist rose from the floor and climbed up his legs. He reached the door. His hands gripped the frame. A searing pain shot through his arm.

Wenjie staggered and lost his balance. The air flickered before his eyes. Suddenly, there was a red grid between him and the door. A strange smell reached his nose. Gas. 

to be continued ...