UFO: Enemy Unknown - Plot

Plot

The story of X-COM, set in the near-future at the time of the game's release, begins in the year 1998. The initial plot centers around increased reports of UFO sightings as tales of abductions and rumors of attacks by mysterious aliens become widespread. The nations of the world come to perceive this as a threat and attempt to form their own forces - such as Japan's Kiryu-Kai force - to deal with the crisis, but these efforts are unsuccessful. On December 11, 1998, representatives from some of the most powerful nations in the world meet in Geneva to discuss the issue. From this meeting is born the secret defense and research organization Extraterrestrial Combat (X-COM), over which the player assumes control at the start of the game.

As the game progresses, the player learns more and more about the enemy, their species, mutated creations and technology. It is ultimately revealed that the aliens are led by creatures of immense mental power called Ethereals, and that their main base in the Solar System is located on Mars, in a region known as Cydonia. Then, the player must prepare the final assault team, attack Cydonia and destroy the mastermind behind the alien invasion, the biocomputer Alien Brain.

The game may end in several ways. If the player's performance is poor for two consecutive months, the player runs a deficit for two consecutive months, all the player's bases are captured, or the player mounts an assault on the aliens' Mars base and loses, the game ends in defeat. If, however, the player is victorious in the final attack, the game ends in mankind's victory.