In the futuristic era of 220X, humanity thrives on radio-wave technology, linked by the expansive Wave Road. Following a tragic space incident that took his father, young fifth-grader Subaru Hoshikawa encounters War-Rock, an otherworldly radio-wave entity from a distant FM world. With insights into Subaru's father's fate, War-Rock becomes the target of various alien pursuers. Collaborating, the duo combines into Rockman, a powerful radio-wave warrior navigating the Wave Road to combat malevolent radio-wave viruses and FMs endangering Earth.