The man in white is a mysterious, unnamed figure who appears briefly in the film OOO, Den-O, All Riders: Let's Go Kamen Riders. His most notable action occurs at a pivotal moment during the climax of the story, when he throws the OOO Driver back to Eiji Hino, allowing Eiji to access new Rider powers and continue fighting against the Great Leader of Shocker. This act is described as that of a Chekhov's Gunman, a character whose seemingly small or unexplained appearance proves to be essential to the resolution of the conflict. The man in white does not speak or engage in combat, and his identity, background, personality, motivations, and relationships are not explored or explained within the film. He appears solely to deliver the artifact at the critical moment and then fades from the narrative, leaving his nature and purpose entirely ambiguous. No further details about his development or abilities are provided.