Loosely based on the Japanese series by Osamu Tezuka, Astro Boy received mixed reviews by viewers and critics alike. Some believed the futuristic film set in a city that floats above a polluted Earth too political. Director David Bower's film depicts Metro City, suspended above the Earth. The only inhabitants left on Earth are Robots cast away as broken pieces of scrap. Dr. Tenma presents his guardian robot, the Peacekeeper, to the president of Metro City. Not to be outdone, his colleague, Dr. Elefun, presents the power of two star fragments with a red and blue core to President Stone. When President Stone places the red core into the Peacekeeper, it begins to attack. Dr. Tenma raises a shield blocking the Peacekeeper in a separate room. Unbeknownst to him, his son Toby left school early to see the presentation and was hiding behind the Peacemaker. Toby is instantly obliterated, leaving his father in complete dismay.
Unable to cope with the death of his son, Dr. Tenma builds an exact robot replica of Toby. Using DNA from his son, he gave the robot Toby's memories. Unfortunately despite every effort to replace his son, Dr. Tenma realize that nothing can take the place the place of his beloved Toby. Confused and unaware that he is not Toby, Astro begins discovering abilities that he has, but soon finds out that Dr. Tenma plans to deactivate him and banish him to Earth.
He makes friends with a group of misfit children. Among them he meets Cora, a runaway from Metro City, her robot dog, Trash Can, and their caretaker, Hamegg. When Hamegg discovers Astro is a robot, he puts him in the Robot Games, giving him no choice but to fight all the robots.
Unknown to everyone, Astro Boy holds the key to destroying the Peacekeeper, restoring Metro City and winning Dr. Tenma's love.