With their most formidable foe vanquished, Inuyasha and his comrades begin returning to their everyday lives. But their peace is fleeting as another adversary emerges: Kaguya, the self-proclaimed princess from the Moon of Legend, hatches a plot to plunge the world into an eternal night of the full moon. Inuyasha, Kagome, Miroku, Sango and Shippou must reunite to confront the new menace.

Kagome Higurashi is a modern day young girl who lives with her family by the old Higure shrine. Unbeknownst to Kagome, she is the reincarnation of priestess Kikyo and posseses the "Jewel of Four Souls" (the Shikon jewel). One ill-fated day, Kagome locates an ancient well near her home and is abruptly transported through the well and into a feudal Japan, inhabited by demons. There, she encounters Inuyasha, son of a powerful demon father and a human mother, who is pinned to a tree by an enchanted arrow.

A ship runs aground on a mysterious atoll leading to an investigation by insurance representative Kusanagi, who discovers an ancient bead that he gives to his daughter Asagi. Meanwhile, ornithologist Nagamine investigates reports of a new species of large bird named Gyaos. As the Gyaos begin to attack, an ancient guardian with a bond to Asagi emerges.

Yamada is the old mistress of a prestigious all-girl high school, who finds a natural enemy in Kamizaki, an outgoing first-year student. However, during Yamada's blind date, their bodies are inexplicably switched