Naraku: Trap of Darkness is twenty-second episode of InuYasha: The Final Act.
- The group has been splintered by Naraku; each has a fear in their heart that torments them, and Naraku intends to use this fear to destroy each one of them.
- Inuyasha becomes possessed by Magatsuhi, but resists his possession through his love for Kagome.
- Sesshomaru kills Magatsuhi with Tenseiga.
Separated from the others, Sango and Miroku wander in search of Naraku's main body as that is where the Shikon Jewel will be. Sango can hear the wind blowing from Miroku's Wind Tunnel, even as it is covered. She knows that he doesn't have much time left. They notice a mist appearing around them; Naraku is setting up an illusion. Miroku and Sango notice they are now at Mushin's temple, where a man similar to Miroku is bidding good-bye to Mushin and a boy who looks like Miroku. Miroku says the man is his father, meaning the boy is Miroku himself; Sango is shocked by this. Miroku wonders what Naraku is doing, as he's relived this tragedy many times in his memory. Once at the very spot where his grave would be, Miroku's father starts being sucked into his Wind Tunnel. Young Miroku tries going to his father, only to be stopped by Mushin, who warns that he'll be sucked into the Wind Tunnel as well. A bright light flashes and all that remains of Miroku's father is the hole the Wind Tunnel created.
The illusion ends, and Sango breaks down, crying; she asks Miroku if his father truly died such a horrible death. Miroku realizes Naraku was after her, not him; she hadn't seen the fate of those cursed by the Wind Tunnel before now. Miroku tells Sango that staying still is just what Naraku wants; they mount Kirara and try evading Naraku's attacks. However, Naraku prevents Kirara's flight, knocking them to the ground and focusing his attacks on Sango, forcing Miroku to open his Wind Tunnel, despite her protests. Miroku knows that when his hand finally tears open, Sango will be at risk too. He bids her farewell, running off to die alone. Sango tries to follow on Kirara but cannot find him.
Kagome awakens at the bottom of the pit where she had been pushed by Inuyasha. She finds that Sesshōmaru is next to her, killing the demons who are trying to attack her. Sesshōmaru quickly deduces that Inuyasha was consumed by Naraku's darkness and transformed into his demon form; Kagome follows after him to find Rin. Upon seeing what appears to be her, Kagome is told it was nothing more than an illusion. Sesshōmaru feels insulted by Naraku's tricks, but knows he cannot use Bakusaiga as Rin could be used as a shield.
Meanwhile, Inuyasha wanders aimlessly, remembering his parting with Kikyō fifty years ago; he promised he would protect her this time, but failed when Naraku succeeded in killing her a second time. This snaps Inuyasha out of his demonic mind-set, then smells Kagome's blood on his hand. Naraku taunts Inuyasha, saying that he has done it again; Inuyasha killed the woman he loved, just like before. Inuyasha begins convulsing in pain as Naraku says he will grant salvation by removing the human heart in Inuyasha, which is what the Shikon jewel desires for him.
Elsewhere, Rin awakens and sees Magatsuhi looming near her. She runs off, calling for Sesshōmaru. However, she bumps into Inuyasha, who Magatsuhi is willing to allow kill her. However, Inuyasha tells Rin not to move and tries hitting Magatsuhi, something that impresses the evil spirit as the human heart in Inuyasha is still holding on. He then possesses Inuyasha, ready to fight Sesshōmaru again. Sesshōmaru, catching Rin's scent flies towards her with Kagome, but Naraku swallows Rin into his flesh. Now without any distractions for his foe, Magatsuhi uses Tessaiga to create a Meidō Zangetsuha. However, Sesshōmaru is too close to dodge it, meaning he's most likely to die from the attack.
While in Kaede's village everyone watches Naraku hovering in the sky (noting that he has become an imitation of the Shikon Jewel), Shippō and Jaken begin to fight over the fact that Jaken did not join Sesshōmaru in battle; Jaken wished to use Shippō as transport to Naraku, Kohaku interrupts them and all three head up to find their friends on A-Un. Jaken explains that only a fool would go into battle against a foe dangerous as Naraku alone; Kohaku is surprised by Jaken's method of asking for things. At that moment a Meidō rips a hole in Naraku's body allowing them to enter.
Inside, Magatsuhi is surprised, realizing that Tessaiga is the final link to Inuyasha's senses; he missed Sesshōmaru because of Inuyasha's interference. Sesshōmaru disarms Magatsuhi, allowing him to complete take control of Inuyasha; the Tessaiga lands above them. Sesshōmaru continues to fight with Tenseiga, being chided by Magatsuhi for not using Bakusaiga to eliminate his host body. Kagome goes to retrieve Tessaiga, nearly falling once again. She holds onto Tessaiga, which is plunged into Naraku. As she holds on, her wound bleeds, allowing Inuyasha to smell the scent and allow him to regain control; he yells for her to give him Tessaiga. Kagome lets go and tosses the sword to him. Inuyasha uses the Wind Scar to create a soft landing for her before heading to check on her.
Magatsuhi has become angered by his inability to possess Inuyasha, deciding to move on to Kagome the moment Inuyasha reaches her; he taunts Sesshōmaru, saying that if he wanted
him to leave Inuyasha, he should have asked. No sooner does Magatsuhi try moving to Kagome, Inuyasha moves away; however, he is too late as a piece of Magatsuhi got inside her. Tessaiga suddenly changes to Dragon-scaled form, producing Inuyasha's demon vortex and Magatsuhi, who has become trapped by Inuyasha's demonic energy and cannot escape to a new host. Sesshōmaru tells Magatsuhi that he chose the wrong person to possess and slices him right down the middle with Tenseiga. Magatsuhi vanishes into nothingness with a scream of agony. Sesshōmaru lands and sheathes his Tenseiga.