Inuyasha the Movie 4: Fire on the Mystic Island

The Cauldron of Resonance releases a green orb that gives life to a look-alike of Kikyō. Four scars appear on the backs of all the demon children except Ai, signaling a dark omen. Asagi quickly realizes the danger and urges Ai to flee while the others prepare to react.

Asagi tells Ai to head for safety away from the island. Inuyasha, Kagome, Miroku, Sango, Shippo, and Kirara intervene to protect Ai from the emerging threat. The rescue solidifies the group’s resolve to uncover the mystery of Hoarai.

Inuyasha recounts how Hoarai appears only once every fifty years and foreshadows the danger posed by the Four War Gods. He connects the current reappearance to events from fifty years earlier involving Kikyō. The tale sets the group on a cautious path toward the Cauldron.

In a flashback, the Four War Gods ambush Inuyasha and Kikyō on Hoarai Island. Gōra drains Kikyō’s blood to create her doppelgänger, while Ryūra marks Inuyasha with four scars. The attack explains the origins of the current crisis and the enemies’ power.

As the island reappears, Kikyō decides to investigate its mystery, while Sesshomaru deviates from his group to confront Kyōra, who had given him his scars in the past. The rival confrontations elevate the stakes of the unfolding events. The pair split their attention between personal history and the present threat.

Jūra fires a Thunder Cannon at the advancing group. Miroku and Sango ride Kirara to deter the attack, while Inuyasha, Kagome, and Ai retreat to the island shore and encounter Ryūra. Kagome’s intervention saves Inuyasha from Ryūra’s assault, shifting the momentum of the encounter.

The group reaches a village where they meet the children and learn that Asagi intends to sacrifice herself at the Cauldron to buy more time for the others. The vow to shield the others deepens the group’s resolve to stop the War Gods. They resolve to follow Asagi to the Cauldron.

The group follows Asagi toward the Cauldron, and during the attempt to destroy it, Inuyasha and Asagi are pulled into the depths of the Cauldron. The external world fights to keep the doors open as danger closes in. The internal struggle marks a turning point in the battle against the War Gods.

Inside the Cauldron, Lady Kanade reveals how past efforts failed and why the War Gods always regained power. She explains the power spheres’ role and sacrifices, then entrusts Inuyasha with a box containing the four spheres and her remaining strength to break the Cauldron. Her offer hinges on Inuyasha destroying the Cauldron and saving the children.

Inuyasha and Asagi free themselves and destroy the Cauldron, breaking Kagome’s bow and arrow in the process. The destruction frees powerful energies that begin to shift the balance of the island’s danger. The immediate threat intensifies as enemies react to the Cauldron’s collapse.

As the Cauldron collapses, the Kikyō doppelgänger emerges from the orb and steals the power spheres, releasing them to the Four War Gods. This act restores their threat and forces the team to split up to counter multiple fronts. The group’s unity is tested as the battle lines realign.

Inuyasha confronts the doppelgänger, while Miroku and Sango ride Kirara to battle Jūra and Gōra. Kagome, Shippo, and the children attempt to build a raft to escape, only to be blocked by Ryūra. Sesshomaru takes on Kyōra, and the others push through the onslaught to protect the group.

The real Kikyō arrives and destroys her doppelgänger, then leaves behind her bow and arrow as a symbol of renewal. Inuyasha is saved by Kikyō, whose arrival shifts the tide of the battle. The reunion underscores the stakes of reclaiming power from the War Gods.

Kagome’s sacred arrow and Inuyasha’s Backlash Wave combine to destroy the final War God formed from the power spheres. The scars on those marked are removed as the threat dissolves. The island begins to collapse as the group makes their escape on a raft.

With the threat vanquished, the children temporarily reside in Kaede’s village while they pursue their own freedom. Inuyasha and his friends bid them farewell, promising to meet again, and the group resumes their journey anew. The myth of Hoarai is laid to rest for good.