Germany was divided into East and West after WWII, where citizens of either treated the other side as enemies. In the midst of Cold War, however, the Earth was invaded by an alien life form landed on Kashgar, Xinjiang Uyghur Autonomous Region, known as "Beta." Now, ten years after the first contact, East Germany, formally German Democratic Republic, has become the front line.

A terminally ill girl named Himari Takakura is miraculously saved from death by a strange spirit who resides in a penguin-shaped hat. However, in exchange for extending her life, the spirit tasks Himari's brothers, Kanba and Shōma, to seek out an elusive item known as the Penguin Drum with assistance from a trio of strange penguins.