On August 15, 2023, the heavy rain in Chinatown, Bangkok, just stopped.

Su Chen stood outside the cordon of the Nanyang Treasures Museum, the back of his shirt soaked by the hot and humid air. He looked down at the case briefing on his phone - at six o'clock this morning, the museum's treasure, a Ming Dynasty gilded Buddha statue, disappeared into thin air with the security system intact, leaving only ice crystals all over the ground.

"You bastard, you stepped on my gossip formation!"

The moment the duck's voice exploded behind him, Su Chen was dragged back by a huge force. A thin man in a flowered shirt was lying on the ground, drawing spells with fluorescent powder along the water stains, and the jade Pixiu dangling from his neck was covered in mud.

"This is important evidence." Su Chen frowned and was about to say something, but his sight was blocked by the cell phone that was stretched out from the side. The enlarged surveillance screenshot on the screen said: "The distribution of ice crystals conforms to the Fibonacci spiral. The murderer... ..." The young man in the turtleneck sweater suddenly got stuck, his neck veins bulged, and he stuffed the tablet into Su Chen's hand.

Su Chen's pupils shrank slightly - this stuttering young man was actually Qin Feng, a legendary genius in the international criminal investigation circle, and the one lying on the ground drawing talismans must be his cousin Tang Yu, who regarded himself as "the number one Feng Shui detective in Chinatown".

"Make way!" Tang 꿦 suddenly jumped up, and the compass "slapped" against Su Chen's chest, "This officer has a black spot on his forehead, it's not appropriate today..."

"I'm Su Chen, a forensic technology consultant." He flashed his ID to interrupt the other party, took out a portable low-temperature scanner from his briefcase, and said, "Please give way to the scene for three minutes and two seconds."

Tang Yu's folding fan froze in mid-air, but Qin Feng had already set up the tripod tacitly. As the red light of the laser surveyor swept across the exhibition hall, Su Chen noticed something unusual in the display case in the northwest corner - the inside of the bulletproof glass cover where the gilded Buddha was originally located was condensed with fish-scale-like ice patterns.

"Cold... condensation experiment." Qin Feng suddenly said, turning the tablet towards the two of them. A temperature and humidity curve was jumping on the screen: "During the time of the incident, the air conditioner continued to cool, but the relative humidity dropped sharply from 60% to..."

"It dropped to 18%, which is a sign of a liquid nitrogen leak." The scanner buzzed as Su Chen answered. The holographic projection showed the remains of a metal pipe sandwiched between the floors: "The murderer used liquid nitrogen to create an instantaneous low temperature, causing the surface of the Buddha statue to freeze, and then used a pulley system to transport the ice shell through the ventilation duct."

Tang 꿦 suddenly knocked on the vent with a folding fan: "Water flows in the Qian Palace, and wind hides in the Xun Position! The direction of this pipe is in line with the 'stealing the sky and changing the day' strategy of Qi Men Dun Jia!" He poked Su Chen with his fingertips covered with fluorescent powder, "Little boy, check if there is a freezer at the end of the pipe?"

Qin Feng has already called up the building structure diagram, and his fingertips drew a red line on the screen: "Ventilation duct...pipe connection..." He took a deep breath, his neck flushed, "Cold storage No. 37 in the back alley seafood market!"

When the three rushed into the freezer filled with the smell of fish, Tang 꿦 suddenly opened the freezer door: "Look at me, the master!" He picked up a frozen mackerel as a probe, and the echo of knocking on the pipe wall was particularly crisp in the air of minus 20 degrees Celsius.

"Here!" Su Chen grabbed Tang's wrist. The corner where the frozen fish head pointed was piled with antifreeze film fragments, which were exactly the same as the material found in the exhibition hall. When Qin Feng squatted down to collect samples, Tang suddenly broadcast live to his mobile phone: "Double attack 666, my friends! This is the legendary 'Ice Escape Technique'!"

"Detective Tang!" Su Chen couldn't help but pull his phone away, but saw half a face flashing in the live broadcast screen - it was the screen where the cold storage manager appeared one hour before the incident. This noisy Feng Shui master accidentally intercepted the key evidence.

When the sirens got closer, Qin Feng suddenly turned the tablet towards the two of them. In the enlarged surveillance screen, the administrator's right ear was shining faintly - that was the nano tracker developed by Su Chen, whose prototype paper was published in an academic journal three days ago.

The rainstorm came again, and the three of them stood under the eaves of the cold storage. Tang 꿦 swung a wet folding fan and grinned: "Little 떚, you have some skills in low-temperature scanning, do you want to hang out with your cousin?" Qin Feng silently handed over a tissue, and a line of words was typed on the screen: [Cooperation application has been submitted to the Criminal Investigation Headquarters]

Su Chen looked towards the flashing neon lights in the rain, and a system interface appeared on his retina. The original 71-hour countdown was suddenly reset to [Case Number: 1946-07-16].