The show takes place on a faraway planet called Mobius. An evil, bald, dark-eyed and mustachioed scientist named Doctor Robotnik invaded and conquered a huge and beautiful city named Mobotropolis, with the help of his intelligent but craven assistant Snively and his army of laser-toting robot soldiers called Swatbots. Robotnik then used a giant airship to turn Mobotropolis into a new city renamed Robotropolis, a polluted city of factories and warehouses.
Robotnik soon invaded the castle home of the city's king who mysteriously vanished. Robotnik captured the rest of the citizens, including a brainy old hedgehog named Chuck and his dog Muttski, and used a machine called the Roboticiser to turn them in to robot slaves. Those who managed to escape retreated into the Great Forest to build a village named Knothole to hide from Robotnik. Among the youngest of the citizens were a group called the Freedom Fighters. First there's Sonic the Hedgehog, Charles' speedy nephew. Then there is his best friend Tails, a young two-tailed fox who can twirl his tails to fly. Next, there's Rotor, a walrus with a knack for machines. Next, Antoine, a French coyote with many personality flaws who is the palace guard. Next is Bunnie Rabbot, a pretty southern cyborg rabbit who was almost completely roboticised if not for Sonic. Last is the group's leader, Princess Sally, the king's only daughter.
For 10 years, the Freedom Fighters constantly foiled Robotnik's schemes. In the show's second season, a female dragon named Dulcy was a new star. The show went up to 2 seasons and it got cancelled after the final episode ended with a cliffhanger. There were rumors of a third season but it never aired.