From Toon Zone Animation Wiki
Sonic X is an anime show based on the Sonic the Hedgehog video game franchise. It is the third television series based on this videogame series, being preceded by Sonic the Hedgehog and The Adventures of Sonic the Hedgehog. It loosely follows the story of the Sonic Adventure games, although several original characters were created for the series.
In Sonic X, Sonic and company are transported to Earth by Chaos Control. There they meet a young boy named Christopher. Together with his scientist grandfather, they help Sonic, Knuckles, Tails, Shadow, Amy, and the rest of the gang gather the Chaos Emeralds with two goals in mind: 1) Prevent Eggman from getting them to use himself and 2) Find a way home.
Sonic X was divivded inth three seasons for the US broadcast. At the end of season 2, the gang is sent back home. In season 3 Chris is grown up and has invented a machine that will allow him to go to Sonic's world. While it has been years for him, it has o9nly been a few months for Sonic and company. Chris arrives just in time to help with a new mission. Galactic invaders are trying to take over the entire universe, and even Sonic in Super Soni form isn't enough. The third season never aired in Japan, but most people regard it as being the best season of the three.
