The Book of Fish depicts the process of Jeong Yakjeon (Sul Kyung-gu) and fisherman Changdae (Byun John) interacting beyond their social status. Jeong Yakjeon wrote a dictionary of sea life called 'The Book of Fish' on Heuksando Island, an exile site in 1814. Director Lee Joonik developed this project into a human story by unfolding the layers of history through this one book, which contains the essence of practical studies and love for people at that time. There are no spectacular events or provocative situations in The Book of Fish; there is, instead, only a deep and beautiful relationship that forms the story. With the help of Changdae, Jeong Yakjeon practices studies that will help people, but Changdae, who dreams of becoming a Neo-Confucian, becomes frustrated looking at Jeong Yakjeon. Nevertheless, the two men, who are of different ages, social statuses, and philosophies, are gradually reborn as the meanings of each other. The process of reaching the one-line phrase, ′When I know my friend deeply, I become deepened,′ is as beautiful as the picturesque landscape. (SONG Kyung-won)