The DarkZide stealthily appeared on Earth from their dying world in Dark Dimension to acquire the Larmu, human life-energy, to continue their existence. To counter the threat, Takeshi Munakata of the Cabinet Secret Service established the group SAIDOC to intercept the DarkZide. SAIDOC developed the Crystal Power needed to complete the Changérion project. However, the power was accidentally transferred into the body of detective Akira Suzumura.
