Japan, 1944. Trained for intelligence work, Hirō Onoda, 22 years old, discovers a philosophy contrary to the official line: no suicide; stay alive whatever happens; the mission is more important than anything else. Sent to Lubang, a small island in the Philippines where the Americans are about to land, this role will be to wage a guerrilla war until the return of the Japanese troops. The Empire will surrender soon after, Onoda 10,000 days later.