I remember seeing a trailer for Okko’s Inn when we went to see Modest Heroes. While I had not heard of it before that point the trailer made it seemed like a fun family-friendly anime film. It definitely feels like one of those titles trying to inherit the spirit of Hayao Miyazaki films that have sprung up since Studio Ghibli is mostly, sort of, kinda, maybe out of the feature-length film business. It has a plucky young female protagonist, a countryside setting, some supernatural shenanigans, and an overall warm vibe. The general audiences anime film is an important niche for the medium so it is good to see more studios trying to fill the void. I love me my genre trash, shonen spectacle, and high concept anime movies but something with a broader appeal helps keep the industry healthy.
For some reason, I assumed the movie was an original concept but it is actually based on a series of popular young adults novels called The Young Innkeeper is a Grade Schooler! There is also a manga and a TV series based on the books. As far as I can tell the manga and TV series are a bit more direct adaptation whereas the movie is a more compact version. Also, the movie has some major cast changes when compared to the TV series.
While I cannot compare it to the TV series I can tell you how well the movie version comes off when it tries its version of the twenty book series.