Once again under the supervision of Sonic Team, Sonic X is closely based on the Sonic Adventure-era Sonic, even sharing the same voice actors in the Japanese original. The one major difference is that Sonic and friends are from another, unnamed planet and are transported to Earth through a machine emitting Chaos Control. Once there, they make friends with Chris Thorndyke and his family, who oftentimes is portrayed as Sonic's other sidekick, but constantly in need of Sonic's help. While the first half of series one is an original story, the second half decided to adapt Sonic Adventure, Sonic Adventure 2 and Sonic Battle, making changes as necessary to stay in line with the continuity they created with the first 26 episodes. While this has been the closest the video game version of Sonic the Hedgehog has come to an animated form, there are still significant differences which make Sonic X its own unique world.

Sonic the Hedgehog (Japanese: ソニック・ザ・ヘッジホッグ, Romaji: Sonikku za hejjihoggu), "The Most Famous Hedgehog In The World," is the flagship character for home and arcade game (and former game console) maker Sega. Designed to compete with Nintendo's mascot Mario, the two companies went head to head for over a decade, until Sega pulled out of the home console market.

Sega has made numerous video games staring Sonic since his debut in 1991, spanning five generations of console manufacturing. Through numerous aggressive ad campaigns (the most famous being the touting of "Blast Processing," described as being able to render sprites at extreme speeds but actually referring to the CPU's clock rate), Sonic soon became the most recognizable fictional character in the world, even beating out Mickey Mouse. While his glory days may be behind him, Sonic is still a significant part of gaming, and it can not be denied that he forever changed the gaming world.

Other members of her circle of friends include Miles "Tails" Prower, Knuckles the Echidna, Bunnie Rabbot, Amy Rose, Antoine D'Coolette, Hershey the Cat, Lupe the Wolf, and Geoffrey St. John.

Her Role:
Sally once commanded a ragtag militia called the "Knothole Freedom Fighters" to take on the dictator Ivo Robotnik. However it is revealed as of Sonic 132, Sally is now a royal princess of a now established kingdom and is no longer leading the former rebels behind enemy lines because the kingdom cannot risk their only heir to the throne. According to Karl Bollers, the main writer of the Archie Sonic comic book, there IS no more "Freedom Fighters" as the status quo has changed from a group of "ragtag" rebels to soldiers fighting against Doctor Eggman's terrorism. The soldiers now listen to Sonic more so, even if Sally outranks him; and now that her parents have been reunited, Sally is no longer Knothole's voice of authority.