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This is a pretty thorough spoiler, so if you haven't seen the film, don't read.
[Show spoiler]Kawada then, in a plot twist, reveals that he lied about Keiko and merely kept Shuya and Noriko alive because they trusted him. Kawada then seemingly kills both of them; the soldiers in charge go to check for the dead corpses, but Kitano stops them, ending the operation. Declared the winner, Kawada treks to the school. Kitano has since declared the operation a success, and is left on the island after the government leaves in helicopters. Kawada confronts Kitano, and is soon joined by Shuya and Noriko, who are revealed to be still alive after Kawada disabled their collars to fake their deaths. Kitano is unsurprised to see that Shuya and Noriko have survived, having realized Kawada's plan. He reveals that he had hoped that Noriko would survive, as his daughter, Shiori, hates him—he sees Noriko as the daughter he never had. Kitano then reveals a hand-painted picture of Noriko, smiling and standing among her dead classmates. Not wanting to return home, he orders Noriko to kill him. Shuya eventually does when Kitano threatens Noriko with a gun, which is revealed as he falls to be a water pistol. Following a final conversation with Shiori, over the telephone, in which he tells her one must accept the consequences of hating someone, he dies.
The remaining trio escapes the island on a boat, but Kawada succumbs to his wounds and dies after teaching Shuya how to pilot the boat. As he dies, he reveals that in Shuya and Noriko he accomplished his goal of discovering why Keiko smiled at him as she died—she, like he now, had finally found true friends and was willing to give up her life for them. Shuya and Noriko make it to land, where they become fugitives wanted for murder. Shuya, in the movie's final narrative, explains that the two of them, while still peaceful, will fight if they have to protect each other. Together, they go on the run.