The wet neon lights cast mottled reflections on the asphalt road, and Su Chen stared at the metallic glimmer on the administrator's earlobe. The ceramic shell of the micro tracker glowed coldly in the rain - it was the self-destructive model he had designed, which would release dye when it came into contact with water.

"Hold him!" As soon as Su Chen finished speaking, Tang Xiao had already swung out his folding fan and hit the administrator's knee. Qin Feng took out the evidence bag tacitly and caught the blue-green liquid oozing from the other party's earlobe before it dripped.

The roof of the seafood market was crackling under the heavy rain, and the three of them squeezed into a temporary fish stall. Su Chen dripped the dye liquid into the reagent box, and the molecular structure displayed by the chromatograph was exactly the same as the sample stolen from the laboratory three months ago.

"Inside...inside." Qin Feng typed a red exclamation mark on the tablet and called up the institute's access control records. In the surveillance video, a figure in a cleaner's uniform was lingering in front of Su Chen's workstation, with the little finger of his right hand bent unnaturally - just like the cold storage manager.

Tang 翦 suddenly picked up a saury with a fish butcher knife: "Look at the black gills of this fish, it must have swum through a water area with heavy yin energy!" The tip of the knife cut open the fish's belly, revealing a thin slice of metal that had not yet been digested. Su Chen picked up the slice with tweezers and revealed a honeycomb structure under a magnifying glass - the same anti-freeze film material as the ice crystals in the exhibition hall.

"This is the ballast of an ocean-going cargo ship!" Tang 꿦 took out the charter certificate and slapped it on the chopping board, "My second uncle's fishing boat caught this in the Gulf of Siam last month..." He suddenly got stuck and took out a rusted ship part from his trouser pocket, with the words "1946.7" engraved on the inside.

Qin Feng suddenly stood up, his turtleneck sweater brushing against the chandelier. In the warm yellow light, the water stains on the wall actually formed a complete map of Southeast Asia. His trembling fingers moved along the water marks: "Cargo... cargo ship routes... and Zheng's treasure ship..."

The sound of heavy rain suddenly mixed with the roar of engines, and two black SUVs rolled over the accumulated water and stopped. Su Chen stuffed the evidence into the belly of the mackerel, and Tang took the opportunity to lift the fish basket and put it on his head: "This master will show you a 'fake eye mixed with a pearl'!"

Twelve hours later, Bangkok Police Department Physical Evidence Division.

Su Chen put the frozen dye sample into the mass spectrometer. Outside the glass curtain wall, Tang 꿦 was performing tea art in front of the surveillance camera. Qin Feng suddenly pushed the door open and the ship registration data jumped on the flat screen: "July 1946... On July 16, the overseas Chinese merchant ship 'Hai'an' disappeared in the Gulf of Siam."

The mass spectrometer beeped, and Su Chen stared at the analysis results with his pupils shrinking: "The dye contains deep-sea diatoms, which only grow in the upstream area between 5° and 10° north latitude - exactly where the 'Hai'an' last sent out a distress signal."

When Tang 꿦 kicked the door open and came in, the teapot was still hanging on the folding fan: "The latest news! My third aunt's mahjong partner said that antique dealer Lao K received a marine compass last month!" He threw out a blurry photo, and the "HP" mark on the brass compass's direction scale could be vaguely seen in the reflective light.

The rainstorm had just stopped, and the three of them stood on top of the clock tower in Chinatown. Qin Feng pointed his laser pointer to the southeast: "Old...Old K's pawnshop is right here..." His voice was swallowed up by the sudden river breeze. Su Chen raised his thermal imaging telescope, and the familiar outline of a freezer suddenly appeared in the basement of the pawnshop.

Tang 꿦's compass suddenly turned upside down. He kicked open the rooftop water tank and found half a Hongwu Tongbao coin stuck in the rusted valve casing. The copper-green surface of the coin shone with a strange luster in the moonlight. Su Chen wiped it with a cotton swab, and the dark red rust turned into fresh blood under the action of the reagent.

"This is the 'Blood Money Gua'!" Tang Xiao suddenly said seriously, "My master said that when ancient coins stained with human blood appear in the world, it will definitely..." As soon as he finished speaking, there was a crisp sound of broken glass coming from the direction of the shop.

The thermal imaging figure in Su Chen's telescope was fleeing in panic, and the man's right ear was flashing a familiar metallic light. Qin Feng had already rushed to the fire escape, and the tablet automatically played the pawnshop floor plan. Tang 꿦 pulled out the baton from his trouser leg, and the ancient coin in his palm was glowing with blood: "Today, Xun Palace is in trouble, it is better to catch the thief and avoid blood - young man, follow closely!"

The dark alley was filled with the sour smell of fish sauce. Su Chen's leather shoes stepped through the stagnant water. The remnants of the boat ticket from 1946 were vaguely visible at the base of the wall. On the iron fence at the back door of the shop, the fresh cut marks were still accompanied by the fragments of anti-freeze film - this pursuit that spanned half a century finally showed the first crack on a rainstorm night.