Steam Boy is an animated film directed by Katsuhiro Otomo, a Japanese cartoonist and animation director. It is also Katsuhiro Otomo's second major work after akira, which was released in Japan in July 24.

The story takes place in London, England, during the industrial revolution in the 19th century. On the eve of the first World Expo, a talented scientific teenager named Lei got a mysterious invention called "steam ball" by accident, and an evil organization attempted to recapture the "steam ball" to control the world. In the process, "Lei" met the heroine "Scarlett".