After the death of her father, twelve-year-old Tomoko is sent to live for a year with her uncle in the coastal town of Ashiya. It is a year which will change her life.

The 1970s are bringing changes to Japan and her uncles magnificent colonial mansion opens up a new and unfamiliar world for Tomoko; its sprawling gardens are even home to a pygmy hippo the family keeps as a pet. Tomoko finds her relatives equally exotic and beguiling and her growing friendship with her cousin Mina draws her into an intoxicating world full of secret crushes and elaborate storytelling.