A dark, mature cinematic samurai anime set in Japan’s Bakumatsu era, 1864. Seven supernatural swordsmen and their shadow strategist are sent to intercept a convoy carrying weapons specialist Shiba Genzō and Black Seal No. 7, only to discover a government conspiracy involving human experimentation, ancient spirit-forging, and Lord Kurobane Masanori’s secret military program. Branded fugitives, the Shichiken must unite despite clashing loyalties and expose the truth while mastering Chi, Resonance, and Shinken. Their twelve-episode first arc ends with the team defeating the gravitational demon Zūryoku, saving Kyoto, sharing a hard-won moment of comedy, and learning that Kurobane has begun Phase Two with seven stronger demons.