Kotaro begins to realize the new power he has gained by becoming Kamen Rider Black RX, even as a robotic member of the Crisis Empire has him targeted for battle.
In order to save the son of the Sahara Family from a wind-controlling knight, Kotaro must travel to the Demon World where he discovers the truth about the realm of the Crisis Emperor.
When a childhood friend of his discovers plans for a massive Crisis poison gas weapon, Kotaro must come to his aid and protect him while preventing the plans from falling into the wrong hands.
A girl who suddenly becomes a genius becomes the target for the Crisis Empire due to a secret kept from her by her parents regarding who she really is.
Maribaron decides to use one of Gedorian's weaker monsters to assist in a plot to brainwash humanity by manipulating the purity of a cactus-loving girl.
Gatezone employs an extremely powerful yet extremely rebellious member of his machine army to use his machine-controlling powers to defeat Kotaro for the Crisis Empire.
Shigeru finds a strange green stone needed by the Crisis Empire to activate their new dimension-switching device as the daughter of the scientist behind it pursues him to get it back.
When Maribaron accidentally kills the Crisis Emperor's cloned daughter, she decides to fix her mistake by abducting the Sahara daughter, Hitomi, as her replacement.
Pursuing Maribaron and Hitomi in the Demon World, Kotaro is forced to fight against the assumed traitor Deathgaron, leading to a sorrowful encounter that awakens a new power in RX.
While still pursuing Hitomi, Kotaro encounters a strange cyborg who wishes to work on his side, but is under the control of a harsh, mind-controlling warrior of the Crisis Empire.
Crisis creates a second sun over Tokyo, forcing the city to burn unless a scientist can develop a special magnetic gun that can eliminate the threat while under Kotaro's protection.
