High in the present-day Caucasus mountains, a tiny family of hominids ekes out an arduous but paradoxically idyllic existence. When they are finally discovered, all are killed save for a young girl who escapes deeper into the forest and transforms into an apex predator. After years of solitary living, she finds a companion and mate in a runaway autistic boy. As they follow the rounds of the seasons, they are oblivious to their peril until they are...