Anzu has just moved to a new town during Obon, a time for families to remember and celebrate their ancestors. Ever since her grandmother Obaachan died, though, Obon has lost its magic for Anzu. She doesn't feel like celebrating.
Escaping the festivities, Anzu chases after a stray dog. She slips and falls down a ridge - to find herself in the Shinto underworld known as Yomi, a place she's heard about in Obaachan's stories. The stray dog, she finds out, is actually the Gatekeeper of Yomi, and he warns her to return to the human realm before it's too late.
Only, getting home is not simple. Faced with the nefarious Queen Izanami and a realm of creatures, Anzu is in a race against the clock. Can she break a curse, free the spirits of other lost children and reach the gate home before sunrise? . . . Or will she be stuck in Yomi for ever?