The Galactic Empire is a powerful space station, once used for defence against evil forces, only believing in power. From the moon of Europe came evil humanoids who took over the Empire and now use the power for the destruction of helpless planets. You are a member of a small group of freedom fighters from Earth, being sent to the Galactica to try and destroy the evil power before Earth becomes it's victim.
Your mission is to find the generator which supplies the power to the Empire and keeps it together, and then destroy it with your laser.
Sounds like somebody's been watching a certain George Lucas-film, hmmmm?