The Sword of Doom (大菩薩峠 Dai-bosatsu Tōge?, "Great Bodhisattva Pass"), is a jidaigeki movie released in 1966. It was directed by Kihachi Okamoto and starsTatsuya Nakadai. It was based on the serial novel of the same title by Kaizan Nakazato (Japanese), reportedly the longest novel ever written in any language.
The story follows the life of Ryunosuke Tsukue (Tatsuya Nakadai), an amoral samurai and a master swordsman with an unorthodox style. Ryunosuke is first seen when he kills an elderly Buddhist pilgrim who he finds praying for death. He appears to have no feeling. Later, he kills an opponent in self-defence in a fencing competition that was intended to be non-lethal, but became a duel after he coerced his opponent's wife to have sex with him in exchange for throwing the match and allowing her husband to win. His opponent finds out about the affair prior to the match, and is shown giving his wife a notice of divorce. His rage at Ryunosuke during the match causes him to take an illegal lunging attack after the judge proclaims a draw, and Ryunosuke, the better swordsman, parries and kills him with one stroke of his bokken. Ryunosuke flees town after killing the man, and cuts down many of the dead opponent's clansmen who attack him as he is leaving. His opponent's ex-wife asks to go along with him. To make a living, Ryunosuke joins the Shinsengumi, a sort of semi-official police force made up of rōnin that supports the Tokugawa shogunate through murder and assassinations.
Through all his interactions, whether killing a man or at home with his mistress and their baby son, Ryunosuke rarely shows any emotion. His expression is fixed in a glassy stare that suggests a quiet insanity.
Eventually Ryunosuke learns that the younger brother of the man he killed in the fencing match is looking for him, intent on revenge. He plans to meet this young man and kill him, but before the duel can take place, two events occur that shake his confidence. In a botched assassination attempt, he sees another master swordsman, Shimada Toranosuke (Toshiro Mifune), in action, and for the first time he doubts that his own skill is truly unbeatable. That same night, Ryunosuke's mistress, horrified by his unremitting evil, tries to kill him in his sleep. He kills her in the gardens, to the ominous cries of their sleeping child inside the house, and flees without keeping his appointment to duel with his pursuer. Later he rejoins the gang of assassins at an oiran house in the Shimabara district of Kyoto. There, in a quiet (and he is told, haunted) room, he starts seeing the ghosts of all the people he has killed. Further, he is haunted by the words of Shimada: "The sword is the soul. Study the soul to know the sword. Evil mind, evil sword." The final blow comes when he realizes that the apprentice oiran sent to entertain him is the granddaughter of the pilgrim he murdered at the film's beginning.
With this realization, Ryunosuke appears to descend into complete insanity. He starts slashing at the shadows of the ghosts that surround him, and then begins attacking his fellow assassins, who seem to number in the hundreds. In one of the longest (seven minutes) and most famous sword fight scenes on film, Ryunosuke kills dozens of gang members in the burning courtesan house as they gradually wear him down with what few wounds they can inflict. Finally it appears that Ryunosuke will surely be killed; bleeding and staggering, his face contorted in rage, he lurches forward, raises his sword once more, and the film ends; a freeze-frame catching Ryunosuke in mid sword-slash.
The film's abrupt ending leaves many plot elements unresolved. The film originally intended to begin a trilogy of films, based on the historical novel of the same name by Kaizan Nakazato. That 41-volume novel encompassed 1,533 chapters and over 5.7 million Japanese characters—considered the largest novel in Japan until the publication of Sohachi Yamaoka's 40-volume serialized novel Tokugawa Ieyasu. The filmmakers wanted to complete the story in later sequels, but these were never made.