The Kwantung Army set up a "bone mark screening" system in Jiapigou, and the degree of blackening of the miners' teeth determined life and death. Geologist Chen Yan sneaked in in disguise and discovered the Japanese military's conspiracy to use uranium ore to refine atomic bombs. He teamed up with female doctor Ye Zhenzhen to create a "life ledger": the number of cavities marked the number of uranium mine trips, and urine imaging was used to map secret passages.
When three hundred miners were tortured by live experiments, they rushed into the mine singing a war song: "Use our bones to contaminate every gram of uranium!"
Declassified files in 2015 revealed: These radiation-corroded bodies, in the dark mine tunnels, used their lives to build a Great Wall of flesh and blood to prevent nuclear war.
