Only the ocean knows our heart.
A documentary producer Kyung-hoon visits Jeju Island to film Jin-ok, a ‘Haenyeo(female diver)’ who is listed on the Guinness world records. At first, she strongly refuses to be filmed somehow, however soon she notices Kyung-hoon’s sincere heart and decides to be in the documentary. As they spend more and more time together for shooting, they open up to each other not only their heart but their deepest wounds related to the ocean. The bond between them shortly grows into love despite their 40-year of age gap.