The story is set in 1963 in Yokohama. Kokuriko Manor sits on a hill overlooking the harbour. A 16 year-old girl, Umi, lives in that house. Every morning she raises a signal flag facing the sea. The flag means 'I pray for safe voyages'. A 17 year-old boy, Shun, always sees this flag from the sea as he rides a tugboat to school. In preparation for next year's Tokyo Olympics, people are destroying the old and believing only in the magnificence of the...