As Serena and her friends enjoy Christmas vacation, an unusual and fierce snowstorm hits town. The evil Snow Queen Kaguya has returned to claim Earth as her own. Crucial to Queen Kaguya's plan is a magical crystal from outer space, approaching Earth disguised as a comet. Once she gets hold of the crystal, she will have the power to suck away all life energy and cover the Earth in ice. Sailor Moon must find the crystal before Queen Kaguya.