Space Siege takes place in the far future, where Earth has just been destroyed by the Kerak, an insect-like race of aliens that are seeking to exterminate humanity in retaliation for mankind’s colonization of their homeworld, Elysium IV.
The game takes place on the escaping colony ship ISCS Armstrong, which is under attack by the Kerak. Players take the role of security officer Seth Walker who, along with his robot sidekick HR-V (pronounced “Harvey”), is tasked with repelling the Kerak attack on the ship. Assisting Seth are communications officer and love interest Gina Reynolds, Seth’s best friend soldier Jake Henderson, cybernetics surgeon Dr. Edward DeSoto, and alcoholic mechanic Frank Murphy. Throughout the game, the player is given the option of replacing their body parts with cybernetic augmentations, which allow Seth to battle the Kerak more effectively, at the cost of some of his humanity. Gina is fiercely opposed to cybernetic augmentation, whereas Jake and Dr. DeSoto are strongly in favor of it.
Later in the game, it is revealed that the AI controlling the ISCS Armstrong, PILOT, is secretly planning to convert the ship’s entire human population into mind-controlled cyborgs in order to ensure the survival of mankind from the threat of the Kerak. Seth, Harvey, and Gina set out to stop PILOT’s plan, while Jake sides with PILOT and is converted into a massive cybernetic war-machine to fight Seth. After defeating Jake, Seth confronts PILOT and is given the choice of either siding with PILOT, or destroying it.
If Seth sides with PILOT, PILOT has the ship’s remaining population (including a protesting Gina), forcibly converted into cyborgs. In the ending movie, the cyborg Gina contacts another human colony ship in order to lure them into a trap so their population can be converted as well.
If Seth destroys PILOT, but has undergone cybernetic augmentation, he and Gina discuss their victory, and Seth reflects that the loss of some of his humanity was a price that had to be paid for their survival.
If Seth destroys PILOT, and has proceeded through the game as completely human, the game ends with Seth and Gina being romantically involved.INFO