The story of WW2 Japanese Army Second Lt. Hiroo Onoda is an amazing one to say the least.
For exactly 10,000 nights (29 years) Onoda survived alone in the jungles of the Philippine island of Lubang with only his wits, training and dedication to see him through.
For the military historian and martial citizen, the study of the “Secret War” in which the Japanese had trained Onoda in the Nakano School is worthy of attention.
When Japan realized the War had been lost (around late 1943) The focus shifted on training soldiers (and some civilians) in the fundamental aspects of guerilla warfare and sabotage. The Japanese were planning to resist with a guerilla army both in the home islands and abroad.
Just a FYI: The Movie is rather long, coming in a just over two hours and forty-five minutes and is in French with English subtitles.