Alpha 5 is depressed. He receives a distress signal from his creator, King Lexian, deposed ruler of the peaceful planet called Edenoi. Edenoi has been taken over by the evil Count Dregon and his minions. As a favor to Alpha, the Power Rangers take a trip to Edenoi (sans Kimberly, who is currently bed-ridden with the flu).
Once there, they bump into Dregon's Plague Patrol. If that wasn't bad enough, the rebels fighting against Dregon's forces think the Rangers are bad guys!
The rebels are led by a super-powered bug-armored warrior called the Masked Rider. This misunderstanding doesn't last long, but between Dregon's forces and Edenoi's instability due to all of the poison gas mining nobody is safe!