The events of Terminator Zero take place in two time periods. In a desperate bid to alter the course of history, the resistance sends a soldier named Eiko back to 1997 to gather crucial information from a cornered Terminator. This intel allows the resistance to prevent a catastrophic nuclear attack planned by Skynet, the AI that controls the machines. Meanwhile, a scientist named Malcolm Lee works on developing Kokoro, a new AI designed to assist humanity.