Information

Halo 2 continues the story of the Master Chief, the genetically enhanced super-soldier who is the only human ever to successfully defy the Covenant, a coalition of alien races on a murderous march toward Earth. To the mysterious leaders of the Covenant, the human victory at the ancient ring structure known as Halo was an unacceptable failure. They will not fail again.

- Official press release from Bungie.

About the story:

From what we can see from the trailer, the Covenant have finally reached earth, and its up to the Master Chief to do what he can. After an impressive tour though a wonderfully detailed ship, our hero fearlessly leaps out an airlock attempting to land on an enemy mother ship. So far, this is the bulk of what  can be deduced from what little we have been shown in the ever too short trailer.

-Webmaster.