It is officially announced today that a live-action film adaptation of Daiju Yanauchi ( Gangking , Seven☆Star )'s coming-of-age manga Gunkan Shonen ( Warship Boy ) is set to be released in Japan on December 10, 2021. The manga was serialized in Kodansha's Weekly Shonen Magazine in 2012, then compiled in two tankobon volumes. Its story follows the 16-year-old protagonist, Kaisei Sakamoto, who lives in a town with a view of Gunkanjima Island in Nagasaki, and his father, Genkai, who runs a ramen shop. Kaisei, who has lost his beloved mother and is constantly quarreling with others, and Genkai, who has lost his wife who was his childhood friend is immersed in alcohol, are bickering with each other. One day, Kaisei gets caught up in a big incident... The protagonist Kaisei is played by 25-year-old Kanta Sato , a member of Gekidan EXILE, while his father Genkai is portrayed by 58-year-old Masaya Kato . And Yuki Saito , known for his directorial works for the Japanes