A reunion between two estranged sisters gets cut short by the rise of flesh-possessing demons, thrusting them into a primal battle for survival as they face the most nightmarish version of family imaginable.

Sam, a fearless young girl raised outside of her Māori culture, is determined to fulfill her mission of connecting with her mountain. She hopes it can heal her from the cancer she is battling. Along the way, she meets some misfits and new kids in town, and together they journey through a difficult route, discovering the true spirit of adventure and the magic of friendship.