Superdog was originally an ordinary beagle serving in the police force. He was dismissed because of a serious mistake during the execution of his mission. The beagle wandering on the street was caught in an animal research institute, where the evil Dr. Simon (played by Peter Dinklage) conducted experiments on stray dogs in the hope of creating a superdog. The beagle made a mess in the laboratory, accidentally became a superdog, and escaped. A security guard at the institute met Superdog when he was off work and took it home, hoping to improve his relationship with his son. At home, Superdog discovered that he was not only powerful and fast, but also able to speak and fly. Encouraged by the son of the security guard, Superdog decided to use his power to serve the society. At the same time, the evil Dr. Simon was thinking about how to take Superdog back and was planning a sinister conspiracy...