A sudden snowstorm has hit Tokyo, marking the return of an ancient being named Princess Snow Kaguya! She has a chilling plan to freeze Earth, but it requires the recovery of a missing piece of her ice crystal. After falling ill due to the cold, Luna is rescued by a kind-hearted but misunderstood astronomer, Kakeru, who happens to have the remaining shard of the crystal! Called into action to protect Luna and her newfound crush, Sailor Moon and her team of Sailor Guardians are now the only hope the world has of avoiding an eternal Winter!