"Rockman.EXE: Hikari to Yami no Program" is a two-episode OVA that serves as a side story to the "Rockman.EXE" (MegaMan NT Warrior) anime series. The narrative revolves around Netto Hikari (Lan Hikari in the English adaptation) and his NetNavi, Rockman.EXE (MegaMan.EXE), as they confront a new threat in the cyberworld. The story begins with the discovery of a mysterious program known as the "Dark Program," which has the potential to corrupt and destroy the cyberworld. Simultaneously, a "Light Program" is introduced, designed to counteract the Dark Program's destructive capabilities.

The plot intensifies when a rogue NetNavi named ShadeMan.EXE, manipulated by the Dark Program, begins wreaking havoc. ShadeMan.EXE's actions threaten not only the cyberworld but also the real world, as the corruption spreads. Netto and Rockman.EXE, alongside their allies, must navigate the complexities of the cyberworld to locate and neutralize the Dark Program before it causes irreversible damage. The narrative explores themes of balance between light and darkness, as well as the ethical implications of powerful programs that can alter both digital and physical realities.

Key characters include Netto Hikari, a determined and resourceful young boy who serves as Rockman.EXE's operator, and Rockman.EXE himself, a courageous and loyal NetNavi. Their partnership is central to the story, showcasing their unwavering resolve to protect both worlds. Other notable characters include Enzan Ijuin (Chaud Blaze) and his NetNavi, Blues.EXE (ProtoMan.EXE), who provide critical support in the battle against the Dark Program. The antagonist, ShadeMan.EXE, serves as a formidable foe, embodying the chaos and destruction that the Dark Program represents.

The OVA maintains a fast-paced narrative, blending action, suspense, and moments of character-driven drama. It expands on the established lore of the "Rockman.EXE" universe while introducing new elements that challenge the protagonists in unique ways. The interplay between the Light and Dark Programs serves as a central conflict, driving the story forward and highlighting the stakes involved in maintaining the integrity of the cyberworld. Through its concise yet impactful storytelling, "Rockman.EXE: Hikari to Yami no Program" delivers a compelling addition to the franchise, appealing to both longtime fans and newcomers.