Fukutaro, the former president of a board game company, continues to show up at work even after handing over his position to his son-in-law. Fukutaro grabs anyone he can to repeatedly brag about the same past exploits, which irritates those around him. Triggered by an event, his daughter finally unleashes her unspoken true feelings about his toxic old-age behavior. Although Fukutaro seems sad and apologetic, he secretly plots a counterattack with his five elderly fellows.
An MSDF submarine collides with a U.S. nuclear submarine, crushing all 76 people on board, including its CO, Shiro Kaieda. However, the crew survives. The accident is a cover story to get the MSDF submarine's crew on board the Seabat, a nuclear submarine secretly built by the Japanese and U.S. governments. However, Kaieda loads the Seabat with nuclear missiles and suddenly mutinies and flees.
Shiro Kaieda is appointed the captain of Japan's first nuclear submarine, jointly built by Japan and the United States in top secret. However, he and his 76 crew members go rogue in this story that delves into themes of nuclear war, international politics, and world peace.
Set at the Hotel Royal, situated in the marshland of Hokkaido, Japan, and follows the guests, the family that runs the hotel, and the hotel's staff. Masayo Tanaka is the only child of the family that runs Hotel Royal. She failed to enter an arts school and she now works at the hotel. She does not show her emotions to anyone.
Yui Natsukawa (夏川結衣) is a Japanese actress. She was born on June 1, 1968 in Yatsushiro, Kumamoto, Japan. She is a left-hander (but she writes with her right hand). She has received numerous awards, including the 34th Japan Academy Film Prize as Excellent Supporting Actress for her performance in A Lone Scalpel.