This one doesn't ask you to brace for a threat, and that's the whole point. Doremi, Aiko, Hazuki, Onpu and Momoko go out to Doremi's grandpa's place in the country, and the film just lets them be kids in a landscape that remembers magic better than the city does. The frog stone is the kind of idea only Doremi would do straight: not a weapon, not a plot device, just proof that magic and ordinary people used to share the same fields. Aiko softening toward grandpa lands harder than any transformation sequence, because Aiko is the one who guards her feelings like a Osaka kid with something to protect. And the scrap of Majokai history Doremi picks up recontextualizes the series without a single lecture. Short, warm, and gone before you're ready, like every good summer visit to somebody's grandparents.
Doremi and her fellow witches Aiko, Hazuki, Onpu and Momoko travel to the home of Doremi's grandfather. While staying there, they come across the mystery of the frog stone, a magical spot in the old countryside where magic once mingled. During the visit, Aiko finds her affection for grandpa again, and Doremi uncovers part of the magical kingdom's history. The film is a magical girl story set in the Ojamajo Doremi franchise.