Mo~tto! Ojamajo Doremi Kaeru Seki no Himitsu

Synopsis:

Legends tell of a woman named Mayuri who, in the distant past, threw herself into the river after learning of the death of the man she loved, Zenjuro. A strange, crying frog creature was found near her body, and thus the locals came to honor a Frog Stone they created in the lovers' memory. Doremi, Dot, Hazuki, Aiko, Onpu and Momoko are visiting Doremi's grandparents, who live near Fukuyama Mountain where these events took place. Though the adults insist the children stay away from the mountain during the impending evening of the smiling moon, they go anyways to visit the Frog Stone for themselves; and along the way, the rumors of Fukuyama Mountain start to come true...