The first mecha designed to experience love, David is the "son" of Henry (Sam Robards), an employee of the company that built the boy, and the grief-stricken Monica (Frances O'Connor). David is meant to replace the couple's hopelessly comatose son, but when their natural child recovers, David is abandoned and sets out to become "a real boy" worthy of his mother's affection. Along the way, David is mentored by a pleasure-providing mecha named Gigolo Joe (Jude Law) and a talking "super toy" bear named Teddy. His adventures take him to the Roman Circus-style "Flesh Fair," where mechas are destroyed for the amusement of humans; Rouge City, where Gigolo Joe narrowly avoids capture by police; and finally a submerged New York City, where David's creator, Professor Hobby (William Hurt) reveals the secrets of the boy's creation.