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.
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.