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.

Mass Effect allows you to create your own customizable version of Commander Shepard (or jump in and use the pre-created character) and plunge yourself into the center of an epic science-fiction story. Choose your squad-mates, your weapons, skills and abilities, and customize your vehicles, armor and appearance - you are in complete control over your experience.

In the course of your mission to stop the machine invasion, you may choose to follow the path of the soldier, the tech-specialist, or the biotics-specialist…each of which brings an arsenal of unique yet equally powerful abilities to use against the enemy. Wield a multitude of weapon types with precision accuracy…utilize your technical skill to turn enemy war machines against their creators…or unleash the full power of Dark Energy against your foe with devastating effects.

As you progress throughout the game you will improve your character's skills, abilities, and equipment (including weapons, armor, biotic implants and more) to ensure that you have the means to face the growing threat before you.

The role you choose to play in Mass Effect will have tremendous consequences on the galaxy around you. You will face moral dilemmas in which the decision you ultimately make will significantly alter the fate of civilized life in the galaxy.