In an alternate 1997, a post-apocalyptic society lives in a land nicknamed “The Wasteland” that is littered with trash and ruled by a sadistic and tyrannical overlord named Zeus, who uses a device to grind captives into water. The Kid, a teenage comic book fan, scavenges the wastes on his BMX bike to trade with junk dealer Bagu. After trading for water and his favorite comic book Turbo Rider, The Kid runs into Apple, a mysterious, free-spirited young woman. Frightened by her quirky personality and aggressive attempts to befriend him, he flees to his bunker, only to find she has followed him. When she hands him the comic book that he dropped, he reluctantly allows her to stay with him.
As The Kid teaches Apple his rules on how to survive in the Wasteland, they grow closer, and The Kid develops a crush on her. When one of Zeus’ henchmen kidnaps Apple, she urges him to flee. He narrowly avoids capture when he accidentally discovers the remains of the real Turbo Rider. After taking Turbo Rider’s armor and wrist weapon, he sets off to rescue Apple. At the same time, Frederic, a champion arm-wrestling cowboy, is captured while attempting to rescue his brother. After cutting off Frederick’s right hand, Zeus throws him into an arena with Apple. The Kid arrives to intervene, but his wrist weapon fails to fire due to a low charge. He is then captured and thrown into the arena, where he, Frederic, and Apple defeat Zeus’ warriors and escape.
The Kid discovers that Apple is a robot after seeing her survive a gunshot during their escape. She tells him that she is a friendship model. Because of damage to her circuitry, they contact Bagu, who directs them to the robot graveyard, where they can find spare parts. When Bagu is captured and tortured to death, he reveals their location to Zeus, who sends his henchmen. The Kid and Apple evade capture during the chase, but Apple is decapitated by Skeletron, Zeus’ lead henchman. The Kid attaches Apple’s head to a new robot body and falls unconscious to the graveyard’s toxic fumes. He later wakes to find that Frederic, who now has a robotic hand, has rescued him; Frederick says Apple could not be reactivated. They return to Zeus’ camp to kill him.