A resistance fighter from the future with a bullet in his chest arrives in the current timeline. Sarah is still worried about Cameron while Derek thinks its just a matter of time before she turns bad again. Cameron tells John that he can no longer be trusted anymore since he brought her back. John goes to school but skips class. He meets a girl named Riley and the two have an awkward conversation before going to eat together. Sarah, Derek, and Cameron go house shopping and purchase a new and much nicer home.
The resistance fighter arrives at the new house but is in bad condition. He does manage to tell them to “stop Greenway” and gives them the location (a power plant) and time that it will have to happen. When the three arrive at the power plant, Derek flashes to the future to show us how important that power plant is as a base for the resistance. The three take jobs at the place and Cameron quickly identifies Greenway.
Agent Ellison arrives at the home of Charley and Michelle Dixon. Charlie explains everything to Michelle even about the Terminators and Sarah still being alive. However, he tells her that he doesn’t love Sarah anymore. Michelle doesn’t take it well and slaps him. Agent Ellison tells the two that they will have to leave since it is no longer safe for them.
John has lunch with Riley and the two grow closer. He even invites her to the new house. Sarah tries to get some information from Greenway and sees him fight with another high up executive. Later on, she talks to him at a bar and finds out he has a scar because he had cancer. He blames the power plant and mentions how nearly everyone gets it at some point. This obviously concerns Sarah since Cameron had earlier told her that she would die from cancer in the future. Derek breaks into Greenway’s car but sees a guy break his windshield. He finds out that Greenway has a lot of enemies since he stopped a reactor from going online for safety reasons.
John and Riley are busted by Sarah. She tells him that this is not the time but John wants to start living. Cameron recreates a security badge that she “downloaded” into her brain at the bar. This allows Sarah to get into a restricted area. She goes in a place with hazardous materials and starts to get sick. The boss tells her that she “crapped out” and she is forced to detoxify in a shower. Sarah obviously starts to think that this was the day she got her cancer. Thankfully, the “crap out” was a false reading.
Charley and Michelle leave but Ellison stays behind. At the power plant, Greenway decides that everything is safe. However, Sarah notices that he no longer has his scar and assumes that he is an impostor. Derek finds the real Greenway dead in his house. The reactor goes online and Greenway starts to destroy things to try to create a meltdown (if this resistance base doesn’t exist in the future it would be a huge blow to the good guys). Greenway kills three people before Cameron starts to fight him. She takes a beating but Sarah arrives in time to shoot him. This allows Cameron to push him into some explosive materials. The meltdown is avoided. Cameron stores the Greenway bot in a radioactive materials bin.
Back at home, Sarah finds a bloody handprint that leads her to a bunch of messages written in blood in the basement. Catherine (disguised as a black man) buys up the power plant and pledges to make machines that will prevent errors like this from every happening again.
