A romantic Nikkatsu youth film about three female friends.

Nakano Institution is the so-called ‘Spy School’ where many young men are trained to be excellent spies. They erase their names, families, even lovers to bury themselves in training. Jiro, one of the cadets, successfully seize the secret code of English army to pass the final exam. However, he reaches the crossroad when his fiancee Yukiko turns out to be a spy of the enemy.