The Seekers: The Legend of the Silver Fox and the Fire Wolf
Mio and Nao live in the valley of Krum, above a great river that provides everything they need to survive. As children, their grandfather told tales of the Silver Fox and Fire Wolf, tales everyone else believed were only legends--everyone, that is, but Mio.
When the life-giving river that flows through their village is mysteriously threatened, Mio and Nao set out beyond their valley to find out what has gone wrong. The farther they get from home, they find lifeless trees and skies filled with smoke. The other villagers grow weary of their mission until they are confronted with their childhood legends come to vivid life and have to risk everything to save their home.