In the year 2029, Skynet, a highly advanced supercomputer system, has become self-aware and launched a nuclear apocalypse, wiping out most of humanity. The survivors, who form a resistance movement led by John Connor, engage in a war against Skynet's army of machines.
Desperate to eliminate the human insurgency, Skynet sends back a cyborg assassin, a Terminator (played by Arnold Schwarzenegger), to the year 1984. Its mission is to kill Sarah Connor before she can give birth to her son, John, who will one day lead the resistance against Skynet.
Meanwhile, the future John Connor sends back a soldier, Kyle Reese (played by Michael Biehn), to protect Sarah and ensure the survival of his future self. Reese and Sarah initially clash but eventually come to trust and rely on each other as they are pursued by the Terminator.
Despite its relentless pursuit and superior strength, the Terminator is ultimately defeated by Reese and Sarah, who team up to destroy the cyborg. However, the movie ends with a twist, as Sarah learns that she is now pregnant with John, ensuring that the future war against the machines will still occur.