Around 1934, Indiana Jones saved Kobayashi's life. Two years later, Kobayashi and his men led an expedition into Nepal in search of a lost primitive tribe rumored to be located in the Himalayas. Not only did they discover the tribe, descendants of pre-historic cave-dwellers, but they also encountered a frozen dragon surrounded by stone carvings. The dragon was theorized to be the pagan god of the tribe. While Kobayashi and his men were skeptical that the dragon was real, they ultimately decided to leave it be as it was worshipped by the tribe.
However, word of their discovery got back to Japan and piqued the interest of General Makimura, who saw the dragon as a weapon to use against the United States of America. When Kobayashi refused to lead Makimura and his men to the dragon, the general simply got Kobayashi's colleagues to do it instead.
To repay his debt to Indiana Jones, Kobayashi wrote to the archaeologist explaining his discovery of the dragon and Makimura's intentions with the creature. However, Kobayashi could not live with betraying his country and committed ritual suicide after sending Jones the letter.