is a Japanese anime television series created by TMS Entertainment and based on the ''Sonic the Hedgehog'' video game series published by Sega. ''Sonic X'' initially ran for fifty-two episodes, which were broadcast on TV Tokyo from April 6, 2003, to March 28, 2004; a further twenty-six were aired in non-Japanese regions such as the United States, Europe, and the Middle East from 2005 to 2006. The show's American localization and broadcasting were handled by 4Kids Entertainment—which heavily edited the content and created new music—until 2012, when Saban Brands obtained the rights to the series, and later in 2015 by Discotek Media. It is the fourth cartoon based on the ''Sonic'' franchise, following ''Sonic Underground'' and preceding ''Sonic Boom''.
The plot follows a group of anthropomorphic animals originating from the games—such as Sonic the Hedgehog, Tails, Amy Rose, and Cream the Rabbit—and a human boy named Chris Thorndyke, whom the animals meet after teleporting from their home planet to Earth. While on Earth, they repeatedly scuffle with antagonist Doctor Eggman and his robots over control of the powerful Chaos Emeralds, while also adjusting to their status as celebrities. The final story arc sees the friends return with Chris to their world, where they enter outer space with a newfound plant-like creature named Cosmo and fight an army of creatures called the Metarex.
''Sonic X'' received mixed reviews from critics. Generally, writers criticized its American localization and some of the characters, while being more generous toward its story and aesthetics. The series was very popular in the United States, though less so in its native Japan. The show's merchandise included an edutainment video game for the Leapster, a trading card game, a comic book series featuring an original storyline, and various toys and other items. The phrase "gotta go fast", the title of the show's North American theme song, has survived as a ''Sonic'' catchphrase for over a decade after the show's initial release.
Sonic the Hedgehog attempts to destroy the base of Doctor Eggman and retrieve seven Chaos Emeralds. One of Eggman's robots inadvertently shoots a machine containing the Emeralds, which activates the "Chaos Control" technique. This teleports Sonic, Eggman, and some of Sonic's other anthropomorphic friends—Tails, Amy Rose, Cream the Rabbit (with Cheese the Chao), Big the Cat (with his frog Froggy), Rouge the Bat, Knuckles the Echidna, and the Chaotix (a detective crew comprising Espio the Chameleon, Vector the Crocodile, and Charmy Bee)—to Earth, the parallel-universe version of their world. Sonic is chased by police, escapes into a mansion's swimming pool, and is rescued by a twelve-year-old boy named Chris Thorndyke, who lives there with his movie-star mother Lindsey, corporate executive father Nelson, scientist grandfather Chuck, maid and chef Ella, and butler Tanaka. Chris tries to hide the animals from his family until Cream accidentally reveals them, but they all build up a good rapport with Chris' family and with Chris' friends Danny, Francis, and Helen.
The animals still want to return home, so they repeatedly scuffle for the Emeralds with Eggman, his robot assistants—the hyperactive, attention-seeking Bokkun and the bumbling Bocoe and Decoe—and his larger, armed robots. Eggman plans to take over the world, catching the attention of the unnamed nation's President, so Knuckles, Rouge, and federal agent Topaz work to stop him. The other animals soon join the crusade and, when Eggman is defeated, they are all hailed as heroes.
However, the unfazed Eggman awakens a creature named Chaos from a huge gem called the Master Emerald. The animals fight a losing battle to retrieve the Emeralds until Chaos absorbs all seven and becomes giant, but an echidna girl named Tikal, who entombed herself and Chaos in the Master Emerald millennia ago, emerges to help placate him. After Sonic uses the Chaos Emeralds to become Super Sonic, he defeats Chaos, who returns to the Master Emerald with Tikal.
Shortly afterwards, Eggman finds his grandfather Gerald Robotnik's diary and Gerald's old project Shadow in a military base. After being released by Eggman, Shadow breaks into a museum to steal an Emerald, which gets Sonic arrested. Amy rescues him, but Shadow, Eggman, and the duplicitous Rouge escape to the space colony ARK, where Eggman threatens to use a weapon called the Eclipse Cannon to destroy Earth if Earth does not submit to his rule; he blows up half of the Moon to prove his power. Eggman collects the Emeralds to power the Cannon, but this triggers a program Gerald set up decades ago, which will destroy Earth in hours. Everyone works together to shut it down except Shadow, who is unsympathetic until Chris convinces him. Shadow and Sonic power up using the Emeralds and reroute the ARK away from Earth, seemingly killing Shadow.
Eggman rebuilds the Moon, seemingly out of remorse, but its position shifts, creating a solar eclipse, so he manufactures and sells "Sunshine Balls" to replicate sunlight. Sonic sees through his greedy motivations, and Eggman is arrested for fraud. Bokkun activates a robot named Emerl, who quickly allies with the animals, and Eggman escapes prison. Emerl wins an Emerald in a martial arts tournament involving numerous hero and villain characters, but he goes berserk and begins to wreck the city, so Cream and Cheese have to destroy him.
Later, two government physicists show up at Chris' mansion to announce that the animals' world and Earth were once a single world split in two by a cataclysmic event, but are rejoining, which will stop time irreversibly, and the only way to stop it is to send the animals back home. Tails and Chuck begin to build a gate to teleport the animals back to their own world with Chaos Control, but Chris does not want them to leave. When it is finished and all of the animals but Sonic have left, Chris suddenly shuts the machine down and whisks Sonic into the woods to hide. Sonic is understanding, and Chris' parents find him and promise to spend more time with him. With Chris' approval, Sonic returns to his own planet, stopping the merging of the worlds. However, Chris vows that one day, he will see Sonic again.
Six months later, a race of villainous robots known as the Metarex attempt to steal the Emeralds from Sonic, but he scatters them across the galaxy. Meanwhile, on Earth, where six years have passed and Chris is now eighteen, Chris builds another device to return to the animals' world; he is twelve again when he arrives. A sick plant-like girl named Cosmo lands on their planet and they nurse her back to health, so she joins them, and they all board Tails' new spaceship, the Blue Typhoon. On the Typhoon, they scour the galaxy for the Emeralds and "Planet Eggs" (objects that allow life to flourish on planets, which the Metarex have stolen to depopulate the galaxy) and fight the Metarex at every turn. Eggman joins the Metarex shortly after. Along the way, Tails and Cosmo slowly fall in love with each other. Later, Rouge finds Shadow alive in a capsule on Eggman's ship and releases him. At one point, he saves Chris from the Metarex before disappearing, but he reappears and tries to kill Cosmo, much to Tails' anger. The Metarex's leader, Dark Oak, appears and reveals that the Metarex and Cosmo are of the same species and that they secretly implanted a tracking device in her brain while extinguishing the rest of their kind; she has been an unwitting spy ever since. Chris, Knuckles, and Tails notice that removing the device will likely destroy her sight and hearing forever. Knuckles pushes for it to be removed anyway, but Tails refuses, so the surgery is called off and the battle against the Metarex continues.
The heroes find the Chaotix and Shadow, and everyone heads to the center of the universe, where the Metarex are ominously controlling a planet that is made of water and contains a Planet Egg. After Sonic almost drowns in it, the planet begins turning into a giant seed; the Metarex reveal that, because they have lost the battle, they will destroy the galaxy with this planet. Cosmo sees a vision from her mother Earthia, telling her that she must sacrifice herself to save the rest. She fuses with the giant seed and instructs Tails to use the Blue Typhoon's cannon to fire Super Sonic and Super Shadow at her and the seed and destroy them. He does, in tears the whole time, and annihilates the Metarex. Back on the animals' world, Sonic and Shadow reappear and solemnly inform Tails that they could not revive Cosmo and only found a seed of hers; Cream and Amy try to cheer him up. With a change of heart, Eggman builds a device for Chris to return home but promptly reverts to his old ways after Chris leaves. The series ends with Cosmo's seed sprouting and Chris returning home.
抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』