When Sadao finds out that the promise to join his mother was just a trick to attract him to the island, he devotes all his efforts to finding her himself. At the same time spends the family fortune on building a public park and a western-style youth hostel on lands owned by the family.
Sadao dedicates all his resources after learning that joining his mother's promise was merely a ruse. He searches for her alone while using the family wealth to build a public park and a youth hostel in the family-owned land.