After the Jeep explosion, John's 16th birthday makes him confront the fact that he's destined to be alone. Meanwhile, after Cromartie's massacre, Agent Ellison must face off against both the Feds and his faith.

Cameron and Sarah take the initiative to investigate a nuclear powerplant. Meanwhile, John loses interest in academics, but becomes more popular at school with a new friend's help.

Derek and Sarah must outwit Cromartie after he kidnaps Charley's wife, and they must weigh the consequences in rescuing her. Meanwhile, John finds himself unable to choose between Cameron and Riley.

A software glitch causes Cameron to forget who she is. She goes missing from the Connors and is taken in by a street kid named Jody. Cameron and Jody end up at a halfway house where Cameron meets with a social worker who uncovers some of Cameron’s distant memories. Meanwhile, Catherine Weaver meets with Agent Ellison to discuss his future at Zeira Corp, and Ellison does some digging into Weaver’s past.

John and Derek infiltrate a military academy in order to protect an integral member of the future resistance. Meanwhile, Weaver’s first assignment for Ellison takes an interesting turn of events when he discovers a specter from his own past.

Why would a T-1001 ever need to visit a doctor? Sarah, John and Cameron hope to find out as they track another name from their list. Meanwhile, a woman who Derek once knew in the past surprises him by appearing in the present.

The Connors find themselves on high alert and in odd company after their house is robbed. A Terminator terrorizes Ellison, while another gets dangerously close to John Connor. Derek and Jesse continue to get reacquainted.

Cromartie kidnaps Sarah and races to Mexico to find John. When Derek, Cameron and Ellison discover what has happened, they come to their defense, which leads to one final deadly confrontation with Cromartie.

Sarah finds that the strange dreams she's been having while she sleeps are slowly beginning to creep into her waking life, but she has no idea what the dreams mean for her and John. Derek and Jesse investigate a possible Skynet conspirator.

Sarah's preoccupation with the three dots takes her to a place she believes is holding Andy Goode's Turk. Meanwhile, Jesse's plans have come complications and Weaver makes an important introduction.

Cameron learns that a terminator was accidentally sent back to 1920s Los Angeles, and she tries to find out what happened to him. Meanwhile, John has a run-in with a group of punks while taking Riley home from a party.

Terminators come after a family whose unborn daughter plays an important role in the war against the Machines, and Sarah, Cameron, and Derek try to protect them.

Sarah turns to a UFO convention for answers about the "three dots," more details about Riley's mission are revealed, and Ellison begins working with Catherine Weaver's AI prototype, "John Henry."

While fighting to stay alive, Sarah is guided by the image of John's father. Weaver's attempt to protect John Henry has deadly consequences.

The Connors visit a town connected to the destroyed factory; Weaver sends a man into town in search of a survivor.

Haunted by nightmares of the man she killed in the factory, Sarah checks in to a sleep clinic. When suspicious things begin happening, Sarah suspects Skynet may be using the facility for brain-mapping.

Cameron's glitch resurfaces, resulting in unfortunate consequences for everyone. Riley is afraid that Cameron has discovered her secret.

Jesse has a flashback to a mission aboard her submarine, the Jimmy Carter. John and Sarah make plans to leave their house.

Jesse's submarine mission in the future takes a fatal turn that has unforeseen effects on John, Sarah and Derek in the present. Before heading out, Sarah deals with Cameron and John makes a tough choice.

Fearing for her life, Sarah stashes John in a safe house. Cameron and Derek struggle to work together after she reveals a big secret. John Henry becomes compromised.

When John attempts to rescue Skynet’s latest target he finds himself closing in on Weaver, but at what cost? Game plans change, causing Sarah and Ellison to reunite. Meanwhile, Weaver learns Ellison’s secrets.

Fate is changed forever on the explosive season finale episode! The Connors come face-to-face with Weaver in a confrontation that shakes John to the core and changes his reality. Nothing will be the same.