After living a life of peace John and Sarah once again keep running, leaving behind their life and the people that loved them. A new terminator is sent back to protect John and one is sent back to terminate him. In order to prevent his death and judgment day, John, Cameron, and Sarah hide in the one place nobody will ever think to find them.

Sarah makes contact with an old friend to ask a favor, while John decides to pay a visit to Sarah’s ex and Cameron makes a new friend. Together they infiltrate a resistance safe house and discover they are not alone. Meanwhile, Agent Ellison realizes that Sarah is still alive and a dangerous person from Sarah’s past is reawakened.

Sarah pays a visit to Miles Dyson's widow looking for Skynet's creators. Her search leads her to Andy Goode, a cell phone salesman who also happens to also be the inventor of a chess playing computer known as The Turk. Sarah has to make a tough decision regarding her friendship with Goode. Meanwhile, John and Cameron try their best to assimilate on their first day at the new high school and John is conflicted about his role as a hero. Agent James Ellison finds himself getting closer to the truth.

When Sarah, Cameron and John track down stolen cargo, they become separated from John leading him to discover the future isn’t as safe as he had hoped. Meanwhile, Agent Ellison’s murder investigation leads him to an interesting suspect.

When Sarah’s friend Andy submits his computer into a chess competition, she revaluates his computer’s capabilities and worries where it could all lead. During the chess match, Sarah comes face-to-face with a stranger whose history is closely tied to hers. Meanwhile at school, Cameron gets called into grief counseling and John makes a new friend in shop class. Agent Ellison discovers remnants from a terminator battle.

While in and out of consciousness and fighting for his life, a Stranger flashes back to the year 2027, remembering his life in the future and his personal battle against the machines; meanwhile, Sarah finds herself trying to explain the past to Charley.

While breaking in to Agent Ellison's apartment, Sarah discovers a file on her from her time spent at the mental hospital. This leads Sarah to locate a doomsday convert, named Dr. Silverman. John finds out how Sarah escaped the mental hospital, and Cameron joins a ballet class.

John defends Cameron against a damning accusation by Derek, putting him and Derek at odds, while Sarah finds herself in a business transaction with a mysterious business man. Meanwhile, Cromartie closes in on John and Agent Ellison discovers a nemesis at the agency.

Sarah finds herself in a business transaction with a mysterious business man, who threatens to tell their whereabouts to the FBI. Meanwhile, Cromartie closes in on John and Agent Ellison discovers a nemesis at the agency.