No one wants a dark fate. The themes below are repeated elsewhere all over and all we can do is keep going.
In 1998, three years after destroying Cyberdyne Systems,[a] Sarah and John Connor have retired to Livingston, Guatemala. They are suddenly ambushed by a T-800 Terminator, one of several sent back through time by Skynet, which kills John despite Sarah's attempts to stop it.
In 2020, an advanced Terminator, the Rev-9, is sent back in time to Mexico City to murder Dani Ramos, while a cybernetically enhanced soldier, Grace, is sent from 2042 to protect her. The Rev-9, disguised as Dani's father, infiltrates the automobile assembly plant where Dani and her brother Diego work, but is thwarted by Grace, who escapes with the siblings. The Rev-9, using its ability to split into its cybernetic endoskeleton and shape-shifting liquid metal exterior, pursues them, killing Diego and cornering Grace and Dani. However, Sarah arrives and temporarily disables both forms of the entity using military-grade weaponry.
Dani, Grace, and Sarah retreat to a motel. Sarah reveals that she found them because in the years since John's death she has received encrypted messages detailing the locations of arriving Terminators, each ending with "For John", allowing her to destroy them before they become threats. Grace notes that Skynet and John do not exist in her future, meaning Sarah succeeded in destroying the former after Cyberdyne went defunct. However, humanity's future is threatened by another AI called Legion, originally developed for cyberwarfare, which was built in Skynet's place. When Legion became a threat to humans, an attempt was made to neutralize it with nuclear weapons, resulting in a nuclear holocaust and the AI creating a global network of machines to terminate the human survivors, who organized a resistance movement to counter Legion's onslaughts, and Dani's destiny is linked to their war against it.
Grace traces the source of Sarah's messages to Laredo, Texas. Barely evading the Rev-9 and the authorities while crossing the Mexico–United States border, they arrive at their source, where they discover the same T-800 that had killed John. Having fulfilled his mission and with Skynet no longer existing to give him further orders, the T-800 was left aimless. Over time and through his adaptability, he became self-aware, learned from humanity, and developed a conscience, taking the name "Carl" and adopting a human family. After learning how his actions affected Sarah and being able to detect the location of temporal displacements, Carl began to forewarn her of them to give her a purpose to make amends. Carl offers to join them against the Rev-9 and they prepare to destroy it, with Sarah begrudgingly agreeing to work together for Dani's sake. Anticipating the Rev-9's arrival, Carl bids his family farewell and tells them to escape.
The group seek out a military-grade electromagnetic pulse (EMP) generator from an acquaintance of Sarah's. The Rev-9 catches up with them, forcing them to steal a plane to escape, though the EMP generators are destroyed in the resulting shootout. During the flight, Grace reveals that Dani will become the future founding commander of the resistance before the Rev-9 boards their airplane and temporarily subdues Carl, forcing Grace, Sarah, and Dani to parachute from the plane into a river near a hydroelectric plant, with Carl and the Rev-9 following close behind.
Trapped, the group makes their stand inside the plant. In the ensuing battle, Carl and Grace force the Rev-9 into a spinning turbine, causing an explosion that critically damages the two Terminators. The severely damaged Rev-9 endoskeleton incapacitates Sarah, forcing Dani to confront it herself. A dying Grace tells Dani to use her power source to destroy it. Dani tries to fight the Rev-9 but is quickly overpowered. Carl reactivates himself and restrains the Rev-9, allowing Dani to stab it with Grace's power source. He then drags himself and the Rev-9 over a ledge before the power core explodes, destroying them both.
Sometime later, Dani and Sarah watch a young Grace at a playground with her family, the former determined to avert Grace's death and Legion's rise, before driving off to prepare.
D and her friends.
A pyramid scheme. Guess who is on top.