(1984)

James Cameron directs this science fiction thriller about a futuristic killing machine called the Terminator, which is sent back to the year 1984 to assassinate a young woman named Sarah Connor. The cyborg comes from the year 2029, following a nuclear war which has devastated the better part of civilization. Computer defense mechanisms have turned on their creators, starting another war in an effort to eliminate the human race altogether. Mankind's valiant rebel leader is John Connor, Sarah's son. John is destined to help the human race win this war, and the Terminator is the only thing standing in the way. Sent back to the present, the cyborg must kill Sarah before John is born. It systematically eliminates every Sarah Connor in the city of Los Angeles, but Sarah escapes with the man sent to protect her, Kyle Reese, before the Terminator can get to her. What follows is a massive chase which will eventually end in victory for mankind. (Thanks to Worm Pix for the synopsis.)

Additional notes (Warning -- spoilers ahead):

There was a second level to John's choice in sending Reese back to protect his mother. While Kyle and Sarah are on the run from the Terminator, they share a night of passion and Kyle reveals the feelings he's long held for her. Soon after, unfortunately, Kyle is killed during the destruction of the Terminator and Sarah makes her way to Mexico. It is during this scene, as she thinks about the man she lost and a young boy takes her picture, that we make a shocking discovery -- she's pregnant. Kyle had to go back in time, in order to become John's father.

Links:

Worm Pix's Terminator Home Page: Simple yet comprehensive, including pictures and soundfiles of select quotes. Include some update information on Terminator 3.

Hjelstuen's The Terminator Movies: Poorly updated, but very comprehensive -- paticularly good in dealing with certain time inconsistencies in the movies.

The Internet Movie Data Base: Offers a wide variety of plot summaries and user comments, as well as backgrounds on all the actors and a link to the movie's trailer.