The inhabitants of Earth are visited by an extraterrestrial named Nitros Oxide. He claims to be the fastest racer in the galaxy. He challenges Earth to a game called "Survival of the Fastest". If Earth's driver wins, he promises to leave Earth alone. However, if Oxide wins, he will turn Earth into a concrete parking lot and enslave the Earthlings. In response, the player character gathers all four Boss Keys needed to enter Oxide's spaceship and races him in a one-on-one match. Upon Oxide's defeat by the player character, he leaves Earth. He promises that he will return when all of the Time Relics have been gathered. Oxide faces the player again after all the Time Relics are gathered. After losing once more, Oxide keeps his word and leaves Earth forever. The end credits explains what the characters of the game did after the events of the story. Nitros Oxide himself returns to his home planet of Gasmoxia and hides from society. After years of therapy to cope with his loss, he tries to do unicycle-racing. However, he gets into a bad accident.