A flashback in the future shows a young girl frantically trying to escape from a terminator hot on her tail. As the rapidly heavy footsteps approach, the girl reaches a locked door and proceeds to turn the latch open. A spotlight flashes on her from behind, but she manages to turn the lock and push her way out the door. As she steps out, the view pulls back to show a dilapidated cityscape, with flying Hunter-Killer robots patrolling the skies. She runs but trips on debris. She stands up, but before she can regain her senses, a net shoots out and captures her. The girl struggles with her bonds, to no avail. Light shines on her face, and we see it's Cameron.
In the present, Cameron sits silently in the car, with John driving. He pulls to a stop and calls out to Cameron, but she doesn't respond. He asks if she's all right, and says if she wants to kill him again, he wouldn't mind a headstart. Cameron then replies that if she did, they wouldn't have this conversation. John says that he's going to pick up some stuff from a store and they will meet up later. As Cameron leaves the car and walks down the pavement, John tells her to get some snacks for him.
Meanwhile, Sarah drives away from her house and runs into Kacy Corbin at her front porch, who is having a bout of stomach pain due to her pregnancy, and is also bleeding. Sarah then takes her to the hospital. At the same time, Cameron is wheeling her trolley down the supermarket, picking groceries. She takes a notice to a supermarket assistant using his barcode scanner on some products. As she wheels down the fruit section, she spots some apples and picks one. Looking at the apple, Cameron's gaze diverts to a balloon with silver foil, showing her reflection.
This event sparks a memory in her programming, back to the flashback of the future, where she is trapped under the net. Cameron recovers but her movements become erratic as she continues forward and knocks a whole pile of melons onto the floor. A female customer calls for assistance and asks if she's all right, but she stays rooted to the spot and does not respond. Later, a security guard shines light, into her eyes, asking her if she is under the influence of alcohol or drugs. He asks for her identity card, but she pulls out a roll of money notes. The guard asks for her name and shines the light into her eyes again.
Another memory is revealed, Cameron is being interrogated by Skynet's robots. A female voice asks for her name, but she refuses to give it. The voice says that they will give her one. A terminator endoskeleton strides into view and forces her arm down, burning the same barcode on her like the rest of the human captives. As she hisses from the pain, she blurts out her name: Allison Young.
In the present, Cameron stands quietly in a police detention cell filled with girls about her age. A girl approaches her and asks what she's in here for. Cameron replies that she was in the supermarket shopping but couldn't remember anything. She looks at her arm, which has no barcode, and asks the girl if tattoos disappear that easily. The girl points out her various tattoos around her body. She then introduces herself as Jody. When Jody asks her name, Cameron instead introduces herself as Allison.
In the hospital, Sarah watches the doctor doing an ultrasound scan on Kacy's belly. The doctor finds no traces of hemorrhaging. However she wants to check for fatal blood cells, that the blood is hers and not the baby's. If it is the latter, they might have to do a caesarian section to remove her baby. After the doctor leaves, Kacy says if Sarah's busy, she can leave right now. Sarah asks if Kacy wants to call for assistance from the father of her baby, but she says she will be fine and tells her to go. However, Sarah stays behind.
Meanwhile, John walks through the supermarket where Cameron was there a while ago. He notices the spilled melons and asks a nearby customer what happened. He tells John that a girl freaked out and couldn't remember anything, possibly under the influence of drugs. He then confirms Cameron's description to John, and tells him that the police took her to the station.
Cameron is leaving the station with Jody as the store owner does not want to press charges. The desk sergeant tells Jody to keep out of anymore further trouble. As their belongings are returned to them, Jody spots Cameron's roll of notes and gets an ulterior motive. She asks where Cameron is headed but the latter does not know. Jody then tells her that she's coming with her.
A short while later, John reaches the police station and asks the sergeant where Cameron is. He tells him that she left with one of the street kids, Jody. John then feigns an excuse on Cameron under medication and his mother will get angry with him, and finally asks for Jody's usual hangout.
At the hospital, Kacy describes her feeling of pregnancy, and asks Sarah how she felt when John was born. She tells Kacy that she was in the jungles in Central America at the time, when her water broke. When Kacy asks if her husband was there, Sarah lies that he was there holding her arm tight throughout the ordeal. She only managed to leave the jungle by hitching a ride on a bus, where a tobacco farmer onboard celebrated her pregnancy by giving out cigars to everyone and sang a Spanish birthday song. Kacy asks Sarah to sing out the song and she relents.
As Sarah starts singing, Kacy's husband, Trevor, walks into the ward, asking if Kacy feels all right. She tells her husband that they were awaiting the test results. Sarah and Trevor introduce each other, and Sarah decides to leave. Meanwhile, John is walking through the streets, asking passersby if they know Jody. As Sarah is leaving, she looks into the baby room and smiles. She calls John and asks what he's doing. John lies that he's shopping with Cameron. Sarah tells him that she took Kacy to the hospital, and John inquires after her. He ends the call abruptly after Sarah hears a passerby making remarks at him in the street.
At ZeiraCorp, Ellison attends another appointment with Catherine Weaver. She hopes that Ellison has been considering her job offer. He confirms this, and tells her that he wants to prevent a tragedy like the 20 men under him who has died from the terminator's hands. He continues by telling Catherine that these things are evil. Catherine replies that they are just machines, but Ellison says that he won't make the same mistake of thinking they are human. Catherine then tells him that 2 years ago, she and her husband were involved in a helicopter accident, but her husband was killed. They were flying through Barstow, where a microchip production plant was doing some amazing things. Her husband had 700 hours worth of flying in that particular copter, a model of beautiful and flawless design. Almost flawless, as it still needs a human to fly it. Ellison asks if she means that machines make better decisions than humans. Catherine replies that in the most extreme conditions, even the most calm and careful of men panic. She once again asks for his help in finding one of those terminators, and they will take it apart piece by piece, but doubts they would find evil in there. Ellison does not look convinced.
A flashback shows Allison Young locked in a sturdy cell. She is given food by one of the terminator guards, but she splatters all of it on the wall. In the present, Cameron awakens from this memory, and is sitting inside a fast-food restaurant. She looks intently at the food served and comments to Jody on how much food there is. Cameron watches Jody pick pocketing a pen from a nearby customer and draws a picture of a person on her serviette. Jody tells Cameron that she got an internship at a storefront in Chinatown after she moved here 2 years ago from Michigan. When she found out that her employer was a druggie, she was fired from her unpaid job. After that, she started doing any kind of things for money. She then shows Cameron her finished drawing of a girl.
Their conversation is interrupted when a man calls out to Jody. She tells Cameron that they should go, but the man catches up to her and demands to know where the laptop she took from him is. When she tries to explain, he punches her. Cameron tries to help but is grabbed by the man. She gives the roll of notes to him and tells him to leave.
The pair goes and registers at a teen center to stay for a while there. Cameron fills in her name as Allison Young. She later covers Jody's injuries sustained from the earlier punch with makeup. Jody tells her to lie about everything to the counselor who's going to interview them later. She thanks Cameron for the earlier help and gives her her necklace, saying that from now on, she has got her back.
At FBI headquarters, Ellison meets with a female colleague and ex-wife, Rita, in her office. He wants her to investigate off-record, the particulars and history of Catherine Weaver. Rita asks if he's interested in Weaver, whereby he says it's the opposite. He says that Weaver gave him a job offer, and she asks if he's leaving the FBI. Ellison replies that it's the law of the land. She notices that he's not wearing his cross, and by the way he carries himself lately. She tells him that what happened at the massacre in North Hollywood wasn't his fault. A subordinate comes in with a report for "Agent Ellison", which is actually for Rita. Ellison notes that she still uses his surname, and Rita says it's a beautiful name.
In a flashback, Allison is asked where she's from, by the same female voice that initially talked to her. She doesn't remember. In the present, Cameron answers that she doesn't remember when the counselor asks her the same question. The counselor asks her if she doesn't know what town she's from, and Cameron replies that it doesn't matter. In the flashback, Allison says that it's not there anymore. A flash shows a tiger growling in its cage. In the present, the counselor says that people forget some things as it's too painful to remember. In the flashback, Allison is asked about her life. She tells her interrogator that she lived in a tunnel and ate garbage for dinner. In the present, the counselor says that whatever they discuss is confidential, but if Cameron intends to hurt anyone, she will have to report that. In response, Cameron tells her that she will never hurt anyone. Allison is asked about her family. She notices the open door to the room. She replies that her father was an architect. This interchanges with Cameron saying that he taught her how to draw. Her mother was a music teacher; she would sit for hours listening to Chopin. Allison is asked about the bracelet she wears on her arm. Her sister gave it to her on her birthday. This interchanges with Cameron saying that she had a party at Griffith Park, all her friends were there. However, she and anyone else could not have a birthday party anymore. Allison's interrogator asks why, and she replies that everyone was dead. She then begins to cry.
In the present, Cameron cries, and sees a golden statue of a tiger. Her counselor tells her that it is a Balinese tiger. Cameron asks her if she's seen a real one, but her counselor tells her that it was hunted to extinction in the 1930s. Cameron then asks if she thinks this will happen to humans someday. Allison says she is cold, and her interrogator asks where her home is. Cameron replies that she remembers it was Palmdale. In the flashback, Allison stares very intently at the open door until she makes a break for it. Meanwhile, John asks after Jody at the same fast-food restaurant she was in previously, and a guy tells him that she lives in a halfway house not far from here.
Sarah visits Kacy at her ward later in the day. Kacy tells her that the baby is Trevor's. Their relationship has been on-off for a while. Until she got pregnant with his child, knowing he's here for her, she doesn't know. She wants her baby's life to be perfect, even though she knows it will never be.
Cameron calls Allison's mother, Claire Young, and says that it's her, Allison. However, Allison's mother does not know Cameron. Her counselor takes over the call and asks her about her daughter, but Claire says that she has no daughter, at least not yet, as she's heavily pregnant at the moment. However, she thinks the name Allison is a good name. Cameron stares outside the window sadly.
Later in her room lying on the bed, she tells Jody that her "mother" does not remember her. Jody replies that parents suck, especially mothers. Cameron asks why her "mother" did this, but Jody tells her not to think too much and invites her to go out and have fun. At the hospital ward, Trevor strikes up conversation with Sarah and invites her and John to some family activities. Kacy tells Sarah that Trevor's a cop, and he replies that he's a detective in the LAPD, showing Sarah his badge and gun. The doctor tells Kacy that her blood cells are normal and the baby's fine, and she should be able to discharge tomorrow after an observation.
At the FBI, Rita tells Ellison that Weaver's records turn out clean, no criminal history, no pending investigation from any agency, not even a civil suit. She advises Ellison that he should talk to someone before making the decision to accept the job offer. Rita suggests that maybe he is under some psychological trauma. He refuses this assessment, but Rita feels that he is under a lot of pain. Ellison tells her that they both know that it's not true. He thanks her for the report and leaves.
John finds Cameron and Jody playing games at the teen center, where he is stunned to see Cameron having fun and happily smiling and laughing like a normal human. After Jody goes off to get drinks, John drags Cameron aside and asks what she's doing. Cameron tells him that she was playing Foosball, and John tells her that they have to go home. Cameron asks who he is, and says that she is Allison when John addresses her name. He tells her real name is Cameron and they need to get home before Sarah finds out. "Allison" is freaked out and John realizes that she really does not know who she is. John insists that she is not Allison from Palmdale and she is a robot, a machine from the future.
Cameron is shocked to hear this, and John tells her that he can fix her chip. "Fix me?" Cameron asks, "Why would you fix me?" In a flashback, Allison escapes from her interrogation room and runs through a set of corridors. In her panic, she enters a room and locks the door. When she turns to face the room, she finds that there a lot of human prisoners kept in cages, and they reach out and plead for help. In her confusion from the multitude of voices, she rushes to the other side of the room and tries to force open the latch, and is stunned by the sight of a chimpanzee and tiger each kept in a cage. A bear is kept too, and Allison instead rushes to another exit and climbs the stairs to a hatch, where she finds herself onboard a desolate aircraft carrier. An alarm sounds and lights shine on her. She rushes to the edge and sees the ocean. Without hesitation, she jumps into the sea. As she orients her senses, she finds a net pulling and capturing back up the ship.
In the present, John drags Cameron back, but she tears from her grip. Jody arrives and asks if there's any problem. John lies that he's her brother, but Cameron says she doesn't have any. When John tries to use force to pull her away, Cameron throws him against the wall, shocking the rest of the residents. John is asked by the guard to leave.
In the flashback, Allison is thrown back to the interrogation table. She stares up at her unseen interrogator, which is a Terminator-model of her, Cameron. "You shouldn't have run," the robot says gradually into her own voice. "You're just making things worse for yourself." Allison is shocked to see this, while the terminator comments on her pretty hair. Cameron says that she's not her enemy, but Allison is not convinced. She says she wants to know all about her, and says that she is very brave to have John trust her. Allison says she has no idea what Cameron's talking about. Cameron admires his spirit and determination, and she wants to meet him. Allison retorts that John wouldn't want to meet her. In response, Cameron tells Allison that they're going to kill her and everyone, hunt them down until humans are extinct. Allison angrily asks why they're having this conversation. Cameron replies that some of them don't want that, they want peace. Allison was chosen, not just by John, but also by them. Cameron wants to know where John's camp is.
In the present, Cameron speaks to the counselor, telling her that she thinks she's a machine from the future, an infiltrator in the Resistance, with one objective: to find John Connor. The counselor asks why he's so important, and Cameron replies that John is the one who saves mankind from extinction. The counselor asks what Cameron is going to do when she finds John, and she tells her that she will kill him and hang his head on a pike for all to see. The counselor is appalled by this declaration, and later calls the mental institution for help after the interview. Outside John waits in his car.
Upon returning to her room, Cameron comments on Jody's hair and wants her to tell her about her life. Jody says that she came to LA to start over, however she thinks of going to Portland. Cameron says they could. At the hospital, Trevor asks Sarah about herself and how she came to know Kacy. He thinks that being a cop will make Kacy feel safe, but he isn't sure, as Kacy's afraid of coming with him back home. Trevor gets a call to investigate a homicide and parts ways with Sarah. He tells her that he will be back tomorrow to pick up Kacy.
At the teen center, the counselor leads orderlies from the mental institution to where Cameron's and Jody's room are, but finds that they took off. Ellison visits Catherine Weaver at her office, where she introduces her young daughter, Savannah, who is busy doing puzzles. Catherine asks if Ellison ever wanted kids. He says he did once, but his ex-wife wasn't meant to be. At a private corner of the office, Ellison says that he read the report on Catherine's husband's helicopter report, which says it was mechanical failure that caused the tragedy. She confirms it, but Ellison says that wasn't she seemed to mean the previous day. He thinks whoever writes the report, official or not, isn't always true, and if it's his child who wants to know what happened to her father, he would make sure the official answer is the one he wants her to hear. He thinks she saw what he saw. He concludes by asking Catherine when he starts work.
Jody leads Cameron to rob a large house in the suburbs, with John following in his car nearby. She tells Cameron that it's one of the houses that she used to babysit for the family. With a bit of her strength, Cameron breaks the lock of the front door. Jody takes her to a room with a safe. She claims to have seen the owner opening the safe and knows the code. She opens the safe and tells Cameron to pocket the jewelery. Cameron notices a pendant necklace same as the one Jody gave her earlier. Jody replies that she stole it before. Cameron says that wasn't what Jody said when she claimed to have bought it at a thrift store. She asks what's the big deal, but Cameron insists on knowing how she got the necklace. Finally she relents, and tells Cameron that she neither bought it nor stole it, it was originally hers. The house they are robbing is her parents' house.
In the flashback, the Cameron terminator says that Allison lied about the bracelet, that her sister gave it to her on her birthday. She drops a bunch of the same bracelets on the table in front of Allison, saying that she found them on some of her friends. She asks her why all of them were wearing them. Allison tries to make an excuse, but Cameron realizes that the bracelets are a pass to enter John Connor's camp. She says Allison was intending to send her without the bracelet so as to reveal that she's a terminator. Cameron then grabs Allison by the throat and lifts her up, saying that she lied to her. Allison gives a defiant look at Cameron, telling her that she will never let her get to John. In response, Cameron breaks her neck, killing her. She takes her bracelet. "You already did," she says, and leaves.
In the present, Cameron says Jody lied to her. Jody tries to push this off, but Cameron stops her and demands to know who she really is. Jody says that she got kicked out and her parents pretend that she never existed, and wants to leave now. Cameron asks why, and Jody says there's a silent alarm the moment they broke in. Cameron says she tricked her. Jody tries to leave, but Cameron says she never intended to go to Portland, and wanted to run and leave her to take the blame. Jody says no but Cameron grabs her throat, just like what she did to Allison before. The next scene shows John breaking into the house and sees Cameron standing over Jody's body. He rushes to Jody and demands to know what she did. Cameron tells him that they have to go. John asks if she's killed Jody and the latter suddenly wakes up, gasping for breath. "Apparently not," Cameron replies. The two leave the house immediately.
Kacy wakes up in her ward, asking for Trevor. Sarah tells her that he's on assignment and will pick her up tomorrow. Kacy tells Sarah that she was freaked out by her pregnancy and pretended to be cool about it. She isn't sure about she's going to raise the baby, but says that Trevor would make a good father. Sarah confesses that the part where her husband was with her during her labor was not true, that he had died before she knew she was pregnant. Kacy asks why, and Sarah just wanted to think that it was the way it could have been. But in the end she got through the tough times by herself and so can Kacy. She tells Kacy that she will be right next to her so that she won't feel alone.
In the car as they drive home, Cameron tells John that incident was her last get-out-of-jail-free. John sarcastically agrees with her, very angry at what she did. He notices Cameron's necklace and asks where she got it. She answers that she got it from a thrift store, the same reply Jody told her before. The two drive along in silence.