Ray Steam is a young inventor who receives a mysterious invention called the Steam Ball from his grandfather. However, the O'Hara Foundation wants to use the Steam Ball's power for military purposes. Ray's father allies with the Foundation to build a giant airship called the Steam Castle. Ray and his grandfather work to stop the Foundation and Ray's father from misusing technology for warfare. Ray must protect the Steam Ball from both sides and find a way to save his family and city from the impending conflict over the Steam Ball's power.