Sarah takes her son, John, to a small town in New Mexico, where he befriends the person who will become his protector.

Sarah, John and Cameron infiltrate a resistance safe-house and discover they are not alone; agent Ellison realizes that Sarah is still alive; a dangerous person from Sarah's past reawakens.

Sarah calls on Miles Dyson's widow in her quest to find Skynet's creators; John and Cameron make brave attempts to fit in on their first day at the new high school.

When Sarah, Cameron and John track down stolen cargo, they become separated, which leads John to discover that the future is less safe than he hoped; agent Ellison's murder investigation leads him to an interesting suspect.

When Sarah re-evaluates the capability of Andy's computer, she worries about where it could lead; Sarah meets a stranger whose history is tied to hers; agent Ellison discovers remnants from a terminator battle.

In and out of consciousness and fighting for his life, a stranger remembers his life in the future and his battle against the machines; Sarah tries to explain the past to Charley.