Plot
Nishi is a 20-year-old NEET from Osaka with dreams of becoming a comic book artist. One evening, he runs into his childhood crush, Myon, on the subway. She takes him to her family's yakitori restaurant, where she introduces him to her father, her elder sister Yan, and her fiancé Ryo. Two yakuza, Atsu and a senior yakuza whom Atsu calls Aniki (literally 'brother', a term used by yakuza to refer to each other), enter looking for Myon's father, who had ostensibly seduced and stolen Atsu's girlfriend.
As Atsu threatens Myon at gunpoint, Ryo jumps to her defense, but Atsu knocks him unconscious. Atsu then prepares to rape Myon, who cries out for Nishi. Atsu turns on a terrified Nishi, placing his pistol against Nishi's anus and firing when Nishi finally musters the courage to yell out a threat, killing him instantly. The senior yakuza, offended by Atsu's lack of control, fatally shoots him.
Nishi is sentenced to a limbo where he is forced to watch his death over and over again. He then encounters Kami-sama (God), a being whose physical image changes every fraction of a second. Kami-sama beats and insults Nishi, claiming to have created him on a whim for his own entertainment. He then directs Nishi into a red portal where he will disappear, but at the last moment, Nishi declares he wants to return to life, and runs toward the opposite blue portal. Kami-sama, impressed by Nishi's sheer will to live, lets him escape.
Nishi returns to the moment just before Atsu pulled the trigger. This time, Nishi seizes Atsu's gun with his buttocks, and fatally shoots him. He, Yan and Myon all speed off in the yakuza's car, leaving the father and Ryo—still unconscious—behind. The yakuza follow them, threatening to frame them for armed robbery and murder. The boss has his men lead the trio to a dead end on a bridge, but Nishi steers the car off the bridge, and they are swallowed by an enormous whale.
Inside the whale, they meet an old man, who reveals he is a former yakuza who has been living inside the whale for more than 30 years. He shows them to the elaborate suspended house he has constructed over the 'sea' in the whale's belly. When Nishi's attempts to escape fail, the trio resign themselves to life inside the whale. Yan practices dancing and art, Myon practices swimming (a dream she gave up after reaching puberty), Nishi practices writing and drawing manga, and he and Myon finally become sexually intimate.
When the water level inside the whale begins rising, the old man explains that the whale is likely dying. They concoct a plan to make a motor boat using spare parts and fuel from the car they arrived in. On the day before the final match of the World Cup, the whale returns to Osaka and all four manage to escape.
As the four fly through the air, the film returns to its very first scene of Myon running from the yakuza, only this time her leg does not get caught in the door of the train, and the yakuza is left behind on the platform. This is followed by a lengthy montage, similar to that of the opening credits, showing the histories of the various characters. The phrase "This Story Has Never Ended" appears before the credits roll.
