Hitchhiking on the sea" is a way of traveling through the Seto Inland Sea by boat only. The starting point is Shodoshima Island, and for 72 hours, the group will aim westward. That's the only rule. The destination is simply left to the wind. As they call out to people they meet at ports and frantically search for a boat, they discover the diverse and rich lifestyles of people living with the sea. Businessmen who spend their post-retirement lives on yachts. A father and son are proudly engaged in the fishing industry. A couple who never wants to leave their remote island, where the population continues to decline. Three days of encountering life on the sea.