You just left the space academy to join the Spaceguards, an union to protect international research and exploration of the cosmos. Because you are newbie you start with a simple mission while you are dreaming of getting a job in Skycity, an orbital research institut. But before that you just have to take care of the small research spacestation X5. An easy job you believe, just pushing some asteroids but suddenly unknown forces starts to attack.

With successful finishing you get the job at Skycity which also is under attack. Little more is known about the 'Enemy' but you will try your best to protect the staff and equipment, because than you will proceed to the third mission, the final battle on mars!