Microsoft began its E3 2012 press conference with a long, live action trailer of Halo 4 that transitioned into gameplay.
The live action trailer starts with a speech commissioning the UNSC Infinity, which finds itself sucked into a wormhole, eventually crash landing onto the very planet that Cortana and Master Chief are stranded upon.
In the singleplayer campaign, Master Chief encounters both Covenant who arrive on the planet by flying through the wormhole as well as new synthetic enemies that appear to bear the makings of the Forerunners.
Cortana and Master Chief must make their way to the UNSC Infinity before anyone else arrives, and are hailed by distress calls from the men and women aboard the ship that the hull has been breached by invaders.
Expect to see further reveals of Halo 4 in the coming hours and days. The game is exclusive to the Xbox 360.