Inuyasha the Movie 3: Swords of an Honorable Ruler

After their father Inu no Taishou's death, his swords Tenseiga and Tessaiga were inherited by his sons, Sesshoumaru and Inuyasha. But there was a third blade. While visiting his friend Kagome Higurashi in the modern era, Inuyasha comes across Sounga-his father's forgotten sword. Discovered long ago by one of Kagome's ancestors inside the time-traveling well, the sword had been preserved as a shrine treasure. Yet it soon awakens, revealing a bloodthirsty spirit within. Inuyasha fights to control its destructive power before taking it back to the feudal past, where he clashes with Sesshoumaru, who has always sought the sword. But when Sounga vanishes during their battle, the brothers race to reclaim it, still oblivious to its hidden truth and the destiny their father intended for them.