Su Wan is reborn as a White Mastiff in the snow region. She is imprisoned by mastiff traffickers. Escaping into the snowy mountains, she relies on her human intelligence to outsmart poachers, and is taken in by the ranger Tashi. She guards the pasture, rescues wild animals, warns of avalanches, and assists the Ranger Patrol in cracking poaching cases, growing into a legendary Mastiff King who leads the mastiff pack and guards the snow region.