Detective Juro Iwai steers the Iwai Detective Office with assistants Gorowachi and Kaboko, balancing his public role as a trusted police consultant with covert operations as the vigilante Gekko Kamen. Officially authorized to wield firearms and collaborate with Inspector Matsuda, his sharp intellect and athleticism mask dual identities: the methodical investigator and the shadowy figure who vanishes during crises.

Gekko Kamen’s tactics prioritize non-lethal precision—disarming foes with twin pistols, moon-bladed boomerangs, and shuriken. His signature motorcycle evolves across cases, upgraded with rocket propulsion and concealed gadgets. Costume revisions, like the 1972 adaptation’s sleek helmet and goggles, replace earlier turban designs, while additions such as a bullwhip expand his arsenal.

Guided by the creed "Do Not Hate. Do Not Kill. Let’s Forgive," he spares even kaiju like Mammoth Kong, seeking redemption over retribution. His detective expertise fuels strategic confrontations, merging analytical deduction with calculated vigilante interventions.

Cinematic reboots introduce variations, such as the 1981 film’s George Owara persona, yet retain core traits: a white-masked identity, reliance on agility and weaponry, and absence of supernatural aid. Parodies, like the 1999 gag-anime, humorously reimagine his legacy without contradicting established lore.

Unlike peers driven by wealth or trauma, Iwai’s vigilantism stems from self-imposed duty, his dual life reflecting a commitment to justice rooted in moral integrity rather than personal vendetta or public acclaim.