A police officer that nearly meets a violent death is turned into a cyborg with superhuman strength, speed and reflexes.

In 2100, the newly built Bayside City serves as Japan's premier international port. The Angel Arms Company is established by a former policewoman named Takako, to help wage war on terrorism with armed security suits. When the mayor is assassinated, the women of Angel Arms end up protecting the evil crime-lord Hassan, in hopes that his information will help bring down a global terror ring. Takako's back is to the wall as a band of criminals plot to kill Hassan, and the organization's leader is revealed to be the former lover of Angel Arms' own Alisa.

Heat Guy J chronicles the adventures of a young Special Services officer named Daisuke Aurora and his android partner known simply as "J". The pair live and work in the fictional, futuristic Metropolis of "Judoh" (Jewde), where the understaffed and underfunded Special Services Division of the Bureau of Urban Safety has its headquarters.