Living in London with her family, Carol is the daughter of a famous musician, Lionel Mudagolas. While he is currently having difficulties playing his cello, she occasionally starts to listen an unfamiliar voice calling her name. Wondering if her father's situation might be connected to the bad phase of her favorite band, Gable Screen, and the inexplicable silence of the Big Ben, Carol is suddenly transported to another world. There she finds out that she might be the girl predestined to fight Gigantica, a demon lord who recently brought chaos to this strange land.