The happy reunion between siblings, friends, and lovers aboard the space station Aries is short-lived, as a group of heavily-armed terrorists invades. A majority of crew members and tourists evacuates, leaving a small group of fresh-faced military cadets, their tough-as-nails commander, and a resourceful young officer to survive while trying to keep the terrorists from bombarding Earth with nuclear weapons. Soon, though, both cadets and terrorists realize there’s a bigger threat in their midst, in the form of a traitor with a bio-engineered virus. Making matters worse, the genius officer is taken prisoner, leaving his comparatively average younger brother to lead the underdog effort.