On the remote planet of Edenoi, a young prince by the name of Dex, inherited the powers of the Masked Rider from his grandfather, King Lexion. With these powers, Dex can transform in to the almighty Masked Rider, a hero of justice that defends all that is good and pure against the ruthless tyrant, Count Dregon. It just so happens that Count Dregon is Dex's uncle.
Once Count Dregon and his army conquered the peaceful planet, Dex and his allies were the only ones who dared to defend their home world against Dregon’s forces. Later on, Dex discovered Count Dregon’s plans of heading to the Earth to conquer it as well. Unable to just stand by and do nothing, King Lexian sends Dex to Earth as a line of defense, to foil Count Dregon’s plans.
Upon his arrival, Dex is greeted and befriended by a kind family, the Stewarts. Dex is taken in by the family and is adopted, with the Stewarts teaching Dex how to live like a human and his companion Ferbus by his side Dex is ever vigilant and ready at any moment to become the Masked Rider and stop Count Dregon’s forces from conquering the Earth.
