Tetsu, a middle-aged copywriter working for an advertising agency, used to be a fighter in the student movement. Perhaps due to his setbacks, he continued to lead a nightly life of heavy drinking even after entering society. But one day, he began to see drunkards and "solitary individuals" as if they were double-exposed. A creepy, pale ghost-like face seemed to overlap with them.

Eventually, Tetsu discovers that he is being body-jacked (possessed) by the spirit of a samurai who speaks the Tosa dialect. Who exactly is this samurai spirit, and why does it need Tetsu's body? It seems the purpose of this samurai spirit is to search for people. Specifically, those who have escaped from hell and are committing evil deeds like body-jacking humans on Earth to engage in acts such as murder.

Thus begins the strange collaboration between Tetsu, who is reluctantly cooperating, and the samurai spirit. Returning home drunk every night and falling asleep on the sofa, Tetsu is met with coldness from his wife Reiko and daughter Nana. Even the recent work of Tetsu, a commercial copy for a wedding venue, seems to displease Reiko for some reason. And Nana seems to be followed by a stalker. On top of that, Tetsu's subordinate Joechin strangely comes on to him.

One day, Tetsu's senior from his student days, Yoshioka, commits a violent crime and is arrested. Watching Yoshioka on the TV news, that pale figure... the spirit of the "man slayer"... appears to be double-exposed. Is the spirit of the samurai searching for this "man slayer"? And Tetsu learns that the spirit that has body-jacked him is none other than the leader of the Tosa Kinno-to (Tosa Loyalist Party) from the late Edo period, Hanpeita Takechi, and the one he seeks is the spirit of the famous "man slayer" Izo (Okada Izo).

Furthermore, Izo has threatened to attack the person Takechi holds most dear. Who could that be? Moreover, who is Izo intending to body-jack in order to fulfill this purpose?