Yasuda (Hitomi Matsuda), the Wakagashira of the Takemiya Union Tōjō-gumi, infiltrates the hideout of the Yamashina-gumi's Sakazaki (Junichi Kawamoto), who had been secretly engaged in organ trafficking. Yasuda tries to extract the truth from Sakazaki, but is killed by Detective Hyūga from the Organized Crime Division (Marubō). The blame is pinned on Yasuda, leading to his arrest. Two years later... In Yasuda's absence, the boss of the Tōjō-gumi, Tōjō (Hiroyuki Watanabe), is assassinated by a hitman from the Myōjin-kai. The situation changes drastically. Nikaidō (Tarō Kawano) pressures Yasuda to reestablish his oath of allegiance, but Yasuda firmly refuses. Frustrated by Yasuda's response, Nikaidō makes a certain proposal to the union's chairman, Shimamura (Shunsuke Kariya).
45 years ago, a man was subjected to the experiments of the secret organization Shocker and became a cyborg. Since that day, the man's sole mission has been protecting humanity and justice from the threat of Shocker. His name is Takeshi Hongo, the first Kamen Rider. After a long battle overseas, Hongo hears a certain girl is in danger and immediately returns to Japan. He then meets Takeru Tenkuji, Kamen Rider Ghost, who had been investigating the girl's whereabouts.