In a small clearing, an old woman sits by a fire as she is performing a ritual; as she tosses a little paper into a fire, a man in a castle nearby cries out in pain to the concern of his servants because of the curse and no one can do anything about it. Meanwhile, the old woman's ritual is then interrupted by Kagura, who appears behind her, asks if she is Tsubaki, and says that her master wishes to see her as he needs the help of the dark priestess. When Tsubaki asks what a demon would want with her, Kagura says it would also be about Kikyo and questions her about her grudge against Kikyō, gaining the old woman's interest. Kagura now flies with Tsubaki to Naraku's castle and brings her to him. Tsubaki wants to know why she is here and Naraku says that she fought Kikyō 50 years ago to get the Shikon Jewel. Naraku offers Tsubaki the Sacred Jewel in exchange for her services. Tsubaki then morphs into her younger form and says that this is her real form, however, Naraku realizes that only a demon can maintain this form and suspects that Tsubaki sold her soul to a demon in return for eternal youth. However, the demon had but minor standing, and the woman is still seeking more power. She is happy to help him.

When Kagome exits the well and begins to get out, the invisible demon snake quickly comes up to her and bites her on her ankle. She's confused at what bit her since she can't see anything. Then Inuyasha comes onto the scene, clearly annoyed that she took so long. Kagome then tells Inuyasha that something bit her and points out the direction in which she thinks it went and he runs in the direction in which Kagome suspects the animal to investigate, but when he discovers a large demon and smashes it, only scraps of paper fall which he shows Kagome. They are both confused as to what they are.

Meanwhile, the snake demon that bites Kagome arrives with Kagome's blood at Tsubaki and is happy to see it got her blood, who is apparently trying to create some devilry with it. Tsubaki is brought by Kagura to an old wooden hut to Naraku and the wind ruler disappears. Tsubaki enters the hut and inside she places the jewel on a small pedestal then is clearly preparing to do a ritual. Back at the hut, the group sees that Kagome, who reports being bitten, has no bite mark even on closer examination and is confused. Kaede asks Inuyasha to look at the paper he found. Inuyasha takes out the scraps of paper while Kagome first hands out her presents. Kaede now realizes that it is a Shikigami and at this moment Kagome suddenly has an extremely uneasy feeling. She takes out her jewel shards and realizes that they have turned completely black when the three pieces suddenly break through the glass and enter Kagome's throat. She falls over in the back and her friends are worried about what actually happened. Tsubaki has meanwhile established a connection between the large piece of Sacred Jewel she has and Kagome's shards via Kagome's blood and can presumably bring them under her control in the long run. Naraku appears behind her and says that she shouldn't underestimate Kagome, but she says that Kagome is ridiculously weak. Naraku says that Tsubaki doesn't want to kill her right now. Naraku wants Kagome to suffer and therefore put Inuyasha through another nightmare; revealing he is aware of Inuyasha being in love with Kagome and is using that to torture him.

Back in the hut, the group is wondering what is happening to Kagome. Kaede then realizes that the evil they sensed earlier was someone placing a curse on Kagome. She then thinks that it was a Dark Priestess, Tsubaki who specialized in curses and was able to turn the jewel shards black and make then enter Kagome's body. They then realize that the poison could kill Kagome unless they did something.

Miroku and Sango head off to find and kill Tsubaki. Inuyasha at first demands to go with them, but they insist it is best for him to stay with Kagome to which Kaede agrees. Inuyasha then decides to stay as Miroku and Sango leave on Kirara. As Inuyasha watches over Kagome, she then receives the order to kill Inuyasha. Kagome tries to resist the curse much to the chagrin of Tsubaki and the satisfaction of Naraku who says that since Kagome is the reincarnation of Kikyō, "taming her will take more than a little effort." This causes Tsubaki to remember how Kikyō had been weakened by her love for Inuyasha 50 years ago and she wanted to take the jewel from her, when Tsubaki attempted to hurl a curse at Kikyō to which she sprung back at her because she was still far more powerful than this and a blue web was drawn for Tsubaki's eye. This which caused Tsubaki to bear a grudge against the dead priestess. At the hut, Kaede and Shippō are trying to cool Kagome's fever and leave to change the water. Miroku and Sango further try to find Tsubaki.

Meanwhile, in Kaede's hut, the mood is depressed and when Shippō asks if Kagome will survive, Inuyasha hits him on the head and does not even comment when he sees the serious face of Inuyasha. In front of the hut he asks again without Inuyasha overhearing and Kaede is optimistic, but she knows that Kagome is getting weaker and weaker and Tsubaki knows that too. Meanwhile, Naraku asks Tsubaki if it will take much longer for Kagome to give in to the curse and she says Kagome will soon cave in.

In the hut, Inuyasha can imagine that, too, and is getting increasingly impatient and furious that he is unable to do anything while Kagome suffers. At this moment, Kagome finally caves into the curse and is forced to kill Inuyasha.

When an arrow hits the wood right next to him, Inuyasha turns around and Kagome stands there with her bow, because her body is now finally under Tsubaki's control. A shocked Inuyasha remembers a similar situation 50 years ago with Kikyō. He asks Kagome why she is trying to kill him. Kagome, barely able to regain control of her voice, begs Inuyasha to run away causing him to realize she was being controlled. Tsubaki is annoyed that while she had control of Kagome's body, her mind was still resisting. However, Naraku is happy at the scene and says that Inuyasha is to flee and take the chance to kill Kagome. Inuyasha can hardly wait for Miroku and Sango to finish off the priestess. The scene then switches to Miroku and Sango who are still on Kirara and searching for Tsubaki with the assistance of Katsuki and Vegeta, but a heavy spell fends them off when they see someone approaching through the forest: Kikyō. Kikyō then realizes she knows the priestess who put up the barrier. Naraku is still waiting in amusement to see how Inuyasha reacts to the situation: he can be shot or run away and Kagome will die from it. Kagome still pointing an arrow at Inuyasha begging him to run, and Inuyasha is left uncertain whether to run or to stay. Until Sesshomaru knocks her out, and Kakarot gets rid of the venom.