Luna has lived alone at the bottom of the mountain for as long as she can remember, spending her days collecting gems and returning to the river to replenish her water supply. But now, the river has slowed to a trickle, and a new deer has moved into the area.
There's not enough water to survive.
After a strange dream of mystical powers, Luna sets off on a quest to find out what (or who) is causing the river to run dry. Along the way she meets new animal friends and tries her best to survive the dangers of the wild.