A boy loses everything and finds a cat spirit willing to sit with him in the dark. That becomes the whole story, not saving the world, just three kids learning that grief shared is grief that doesn't swallow you whole. Youkai Watch trades its usual bright noise for something quieter and heavier, and the shift lands because it refuses to make their pain cute or convenient.
In 1960s Tokyo, in the Sakura Motomachi district, a boy named Shin gets by happily despite being poor, until the death of his mother, his only relative, leaves him in despair. Itsuki, a boy who has lost his older sister, comes to his rescue. The two are joined by Tae, a girl who can see yo-kai. Together with Shin's guardian spirit Suu-san, the cat yo-kai Nekomata and other new yo-kai, they form something like a family of their own. Their bond leads them into a mysterious incident as they try to recover the souls of the family members they have lost, and a shocking truth lies waiting. The supernatural comedy film also serves as the origin story of how Lord Enma came to rule the yo-kai world.
