As a lead-in to Halo 4 (which launched this week), 343 Industries and Microsoft Studios created a live-action webseries called Halo 4: Forward Unto Dawn that you should check out whether you're a fan of the game franchise or not.
Forward Unto Dawn is a five-part series that takes places in the year 2525. The story follows Thomas Lasky, a cadet at the Corbulo Academy of Military Science, located on a human-colonized planet. Lasky is struggling to live up to the military legacy of his family, as well as trying to reconcile his feelings about the civil war the United Nations Space Command is currently engaged in with insurrectionists.
If you haven't seen or read anything about this series, I don't want to spoil it for you, because each episode is better than the one before it. Not only does the series bring to life the world of the Halo universe, but it serves as a great introduction to that world for those that haven't played the games. As someone who has played all of them, the series reminded me of why I like Halo so much, and got me psyched for Halo 4.
The entire series is now on YouTube on the Machinima Prime channel, and you can watch the first episode in the player below. For more on Halo 4, head over to the official site here.