Some time in the future, a newly built space colony, Terra Venture, begins its journey into outer space to discover a new planet where the human race can thrive. An adventurous youngster named Leo sneaks aboard, and his life will never be the same. Terra Venture soon encounters a rift in space, leading into the Lost Galaxy. This forgotten galaxy is home to more powerful and sinister evil space aliens than they have ever encountered before, led by Scorpius.
When a visitor from this galaxy enlists the aid of Leo and his friends, they step into the portal and find a village being overrun by Scorpius' soldiers. In order to battle these evil creatures and protect the planet, the heroes pull Quasar Sabers from a stone, and use their powers to become Power Rangers. Leo's brother Mike falls into a chasm, seemingly lost forever. The planet is frozen in stone by Furio, and the Rangers flee to Terra Venture, where the stay to protect the colony from invasion.
When the Rangers freed five gigantic beasts from Scorpius, they returned the favor by helping them defeat monsters, first as beasts, and later as Zords, and as the powerful Galaxy Megazord.
A rogue warrior with a mysterious past had appeared on Terra Venture. His name was Magna Defender, and he was on a mission of vengeance against Scorpius, who had killed his son thousands of years ago. He brought with him the magnificent Torozord. It was discovered that Magna Defender had absorbed Mike's spirit to re-energize himself, which was not allowing him to do evil deeds. Magna Defender finally released Mike just before regaining his honor and sacrificing his life to save Terra Venture.
