Metro City is a sprawling metropolitan city in the future, filled with modern technology and industry. Professor O'Shay is a chief scientist in the city's leading research centre. Upon finding a deactivated child robot, O'Shay reactivates the boy and renames him Astro Boy. Astro very quickly proves to be extremely powerful and advanced, but with the personality of a young boy, and O'Shay adopts him as his surrogate son. Soon, O'Shay builds Astro a super-powered younger sister, Zoran, and together the children become the darlings and cream of technology for the research centre.