In 2029, in the future the world is made where humans must be destroyed. Thats when they started to send back a cyborg or machine to kill all of the Connors. The Connors are the ones who will rebel in the future. The cyborg killed two of the three but, was stopped by a time traveler named Kyle Reese. Kyle tells Sarah who is the last Connor that the cyborg was called the Terminator who was trying to kill her. They were invented by Skynet to destroy all humans.
He tells her that she will have a son named John Connor who will lead the rebeling team in the future. Thats why they sent the terminator back to kill her. So she won't have her son to lead the rebel. This would make the machines win in the future. The Terminator does not feel pian. His mission is to kill the Connors. When Kyle is done telling Sarah everything the cyborg strikes again. This causes a car chase. But, in doind this Sarah gets arrested. The police say her story is crazy and stupid. Thats when the Terminator arrives at the police station and kills most of the police there. Sarah escapes from the Terminator with Kyle.
When they were at a motel Kyle confesses his love towards her and she loves him to. Then the Terminator shows up and Kyle gets shot but, is still alive. Thats when Sarah shot a tanker truck. The cyborg is thought to have been killed. But, the bare metal form rises up and attacks them again. Thats when Kyle put a bomb in the cyborg's stomach and blew off the cyborgs legs but, this also killed Kyle. Then Sarah puts the machine in a machine press and kills it. But, don't worry he will be back.
Basically, the terminator is borderline invincible, and he isn't going anywhere. He will be making his return as a cameo in the upcoming film, Terminator: Salvation. He was the villian in film number one, the hero in film in number two, and again hero in film number three. His character will not be as large as it usually is in Terminator 4, but he will be making his appearance.
In the first terminator movie, the cyborg is sent to kill Sarah Connor before she conceives a future rebel leader, John Connor. Kyle Reese is sent back to save Sarah from the killer cyborg.
In the sequel to the first hit movie, an advanced Terminator called T-1000 is sent back to 1997 where he has to kill young John Conner after the T-800 terminator failed to kill Sarah. Sarah Connor was sent to the mental institution where she claims that cyborgs are coming from the future and destroy mankind. However, this time the reprogrammed T-800 terminator comes back to save Sarah and John from the T-1000. The trio of heroes also plan to destroy the company who is responsible for creating Skynet and the terminators in the first place.
In the third movie, we learn that John Conner, now a young adult, has been living "off the grid." An advanced terminator, the T-X, has been sent back in time to kill those who would become Conner's lieutenants in the coming War between the Humans and the Machines. As fate causes Conner to cross paths with veterinarian Kate Brewster, his future wife, it also alerts the T-X of Conner's whereabouts. Fortunately, another reprogammed T-800 terminator comes back to protect Conner again. The T-800 informs Conner that Skynet still exists and Judgment Day is inevitable, but Conner and Brewster, whose father is in charge of the Skynet defense system, are determined to prevent Judgment Day from happening.
The fourth entry in the series acts as a prequel to the previous Terminator trilogy. In the fourth movie, a half-human, half-cyborg suffers amnesia and tries to find out his real identity. Along the way, he meets young Kyle Reese and the adult John Connor who has yet to lead the Resistance forces. Together, they must stop the cyborgs and other cybernetic organisms from attacking the human survivors.