Five descendants of the people showered with Bio Particles by Bio Robots five centuries in the past have become Biomen. They transform with the Bio Brace and fight using their Super Electronic Brains on their masks. Their Bioswords are equipped with sword and gun modes.

Nemuri Kyoshiro discovers a conspiracy centering around a band of disgruntled samurai wanting to avenge the death of their sensei, a political reformer that pushed for better provisions for the lower classes until he was assassinated by Shogunate agents. Their plot, to set fire to the oil refineries of two rich merchants and unleash a raging inferno that will hopefully burn down the Edo Castle.

Film by director Kenji Misumi

In the book of the world's greatest rogues, the number one man can only be one person.

Young Lord Takenaka stands to succeed his father until a series of violent actions lead his retainers to think that he has gone mad with blood-lust. Never offering any explanation, he continues his seemingly unprovoked attacks until he is sent away from his domain.

Down-on-his-luck veteran Tsugumo Hanshirō enters the courtyard of the prosperous House of Iyi. Unemployed, and with no family, he hopes to find a place to commit seppuku—and a worthy second to deliver the coup de grâce in his suicide ritual. The senior counselor for the Iyi clan questions the ronin’s resolve and integrity, suspecting Hanshirō of seeking charity rather than an honorable end. What follows is a pair of interlocking stories which lay bare the difference between honor and respect, and promises to examine the legendary foundations of the Samurai code.