The galaxy is trapped in an endless cycle of extinction.
Every 50,000 years, an ancient machine race invade s the
galaxy. With ruthless efficiency, the machines wipe out
all advanced organic civilization. They leave behind only
the scattered ruins of technology, destroying all evidence
of their own existence.

Few believe this ancient legend. You, however, know it to
be true. The fight to stop this extinction event has
become the most important mission in the galaxy.

You must act without remorse, without hesitation, and
outside the limits of the law.

It is your mission. As Commander Shepard of the SS
Normandy, you will take your elite recon squad across a
galaxy in turmoil, in a desperate race to stop the return
of an enemy without mercy. To stop this enemy, you must
act without remorse, without hesitation, and outside the
limits of the law. Your only imperative is to preserve the
safety of civilized life in the galaxy - at any cost. You
must become the tip of the spear of humanity, for you
alone know the full extent of what is at stake if you
should fail.