Decades after the sentient artificial intelligence Skynet seized control of the planet in 2022, the resistance continues its fight against the machines. After a fierce battle, Eiko, a guerrilla soldier in Japan, manages to corner a Terminator—Skynet's elite killing cyborg. Eiko extracts crucial details of its plan, enabling the resistance to send her back in time to secure a different future. In August 1997, days before Skynet's impending nuclear attack known as Judgment Day, Malcolm Lee works on launching Kokoro, a new AI model designed to fight for humanity. As Judgment Day approaches, a Terminator arrives in Japan to hunt Malcolm and his children before Kokoro becomes self-aware. Malcolm must prevent his creation from becoming misaligned and reaching the same conclusion as Skynet: the extinction of humans.