Just as A Xuan, the Black Lion, ascends to the throne of the canyon, a chilling threat reaches out from the northern ice plains. The Extreme Cold Emperor kidnaps A Tuan, his younger White Lion sister, who can see heartbeats, intending to use her blood to break a two-hundred-year ice seal. A Xuan heads north into the abyssal ice caves, persuades an exiled snow leopard to switch sides, unleashes a tide of enslaved beasts, and storms the ice city. But he never expected that the Snow Lion who has ruled the ice plains for two hundred years came from beneath a hospital room ceiling, just like him. The Black Lion is the claws, the White Lion is the eyes. Together, the siblings join forces, and the wilderness welcomes a new set of rules.