By the year 2084, only one city on Earth can support human life: Mega-Primus. The rest of the planet has been contaminated from past wars with aliens, resulting in an atmosphere filled with deadly toxins and a completely altered climate. Mega-Primus was built as the solution to this disaster, functioning as a self-contained city that would shield its people from the environmentally ravaged planet.

While everything was peaceful for decades, recent increases in violence and crime suggest that something is wrong. If that weren't enough, sightings of UFOs have picked up and people are starting to flee to other colonies. It's only a matter of time before complete chaos erupts! Sensing this danger, the Senate has secretly agreed to support an investigation to determine if aliens are indeed behind the unrest.

X-COM: Apocalypse is the third game in the X-COM series on the PC, which began in 1994 with X-COM: UFO Defense. You must once again lead the X-COM unit to investigate the mysterious happenings from an isometric viewpoint, only this time it's set within a futuristic city.

Send your squad into various buildings (after first assigning them to vehicles such as hovercars) to either find evidence of the alien presence or engage in combat to retrieve their technology. Your goal is to recover as many artifacts as possible so your scientists can find ways to defeat the aliens once and for all. In a departure from the last two games in the series, the tactical part of the game can be played using either turn-based movement or in real time. ~ Scott Alan Marriott, All Game Guide