It was meant to be a routine daily bus ride to their high school for Watanabe Sheena and her friend Yuk, but when the bus enters a dense fog, the unexpected occurs and the vehicle is transported to another world that appears prehistoric. With the bus driver missing, the only other passengers on the bus in this mysterious world are all high school girls: Izumi, Ayu, Kyoka, Anna, and Jessica. With no cell phone or internet signal, they are completely cut off from their world. To make matters worse, they see hundreds of glowing predator eyes at night, waiting for the girls to make a mistake. How will seven high school girls survive in this treacherous place and return safely to the real world?