When Diancie a Pokémon said to create diamond travels to find Xerneas to help her make a heart diamond to save her home, Ash, Serena, Clemont and Bonnie help her to be safe on the way from thieves.

A camping trip turns into a living nightmare when a blizzard traps four friends in 36 inches of sudden snow - And shrieking alien sounds outside of their tents. A race for life ensues as they are hunted by horrific monsters, discovering a larger alien conspiracy with every terrifying stride.