As the first human Specter – sworn defenders of galactic peace – your mission is to halt the advancing armies of a legendary agent gone rogue. But as you lead your elite team across hostile alien worlds, you will discover the true threat is far greater than anyone imagined.

Three hundred years ago the quarians created the geth, a species of rudimentary AIs, to serve as an efficient source of manual labor. But the geth rebelled against their quarian masters and drove them into exile. Now the quarians wander the galaxy in a flotilla of salvaged ships, secondhand vessels, and recycled technology. Other species tend to look down on the quarians, seeing them as scavengers and condemning them for unleashing a dangerous synthetic life form on the rest of the galaxy.

As the Nov. 20 launch date for “Mass Effect” for Xbox 360 draws nigh, the threat of an alien rogue force looms ever closer. To help unlock some of the secrets and mysteries of the vast universe in the highly-anticipated action RPG, Microsoft and Yahoo! will debut the exclusive television trailer for the upcoming game on Thursday, Nov. 8. On Monday, Nov. 12, the SCI FI Channel and Microsoft will continue its countdown for the retail release of “Mass Effect” by premiering the all-new, two-hour extended episode of “Battlestar Galactica: Razor” in select movie theaters. For those lucky enough to attend the Seattle premiere, Jamie Bamber, who plays Apollo in “Battlestar Galactica,” and show creator and executive producer Ronald D. Moore will be in attendance.

On Tuesday, Nov. 20, the SCI FI Channel will celebrate the launch of “Mass Effect” with the debut of a 30-minute special entitled “Sci vs. Fi: Mass Effect.” Scheduled to air at 11 p.m. Eastern and Pacific, the special will feature more in-depth information about the game, exclusive interviews and exciting behind-the scenes footage.

In conjunction with the special, fans are encouraged to go find all the show times and sign up for the “Mass Effect” sweepstakes, starting Nov. 13, for a chance to win the coveted limited collector’s edition of “Mass Effect.”

Also fueling anticipation for the game is the new “Mass Effect” micro-site, which launched today. The micro-site offers a wealth of “Mass Effect” content in one convenient portal, including the latest news and events on the game, as well as screenshots and special promotional items that no space traveling enthusiast should be without. Music fans will also find the “Mass Effect” Original Game Soundtrack, now available for presale and at retailers on Nov. 20.

From the creators of the critically-acclaimed “Star Wars: Knights of the Old Republic” and “Jade Empire” comes an epic space saga exclusively for the Xbox 360 that spans the entire galaxy. Combining a rich and engaging narrative with intense sci-fi tactical combat, “Mass Effect” features an immersive and cinematic gameplay experience rarely seen before in video games.

Features :

• Immersive RPG: Determine the fate of mankind as you lead an elite tactical strike force as an epic galaxy-wide conflict unfolds. "Mass Effect" will take the player into new depths of an action-roleplaying game, with choice-based gameplay.
• Rich and engaging storyline. While defending galactic peace and earning a position of respect for humanity in the community, gamers will discover that a greater conflict between organic life and artificial intelligence exists. Players' decisions and actions will serve to shape the destiny of all life in the galaxy as you become absorbed in the story that is "Mass Effect," the first game in an epic trilogy from BioWare. They will become the center of an engrossing story as they battle against alien life forms to save the galaxy from threatening armies.
• Player controls the ultimate fate of the galaxy: The player's decisions and actions will serve to shape the destiny of all life in the galaxy, while raising humanity to the pinnacle of galactic civilization via noble means or via tyranny.
• Real-time squad based combat: "Mass Effect" employs a real-time, squad based, tactical combat system. Players will be immersed in intense, challenging and exciting combat.
• Explore uncharted worlds: In addition to the main story arc of the game, players will be able to visit a large number of uncharted, unexplored planets which are not directly tied to the main story. At any time during the campaign, a player can choose to explore one of these planets in an all-terrain rover in order to discover new alien life, resources, ruined civilizations and powerful technologies.
• Digital actors: "Mass Effect" features a huge cast of in-engine digital actors that you will encounter as NPCs, enemies or as party members. Each will have life-like facial and body movements, and an advanced dialogue system will give them engaging personalities.
• Character customization. Players will be able to choose from a variety of stunning, photo-realistic character appearances at the start of the game, and throughout the game can increase various statistics which will have an impact on their performance during gameplay. Equipment, weapons and armor that are acquired during the course of the story will change the appearance of the characters.
• Next-generation gaming defined. "Mass Effect" takes advantage of Xbox 360's hardware providing gamers with exciting new experiences, including photo-realistic, high definition graphics on an epic scale. As the future of gaming goes online, Xbox360 live features, including premium downloadable content and recognition of achievement will be available via the Xbox Live service.

Mass Effect, rated “M” for Mature, will be available in stores Nov. 20, 2007.