The action ramps up in episode 4 of Halo 4: Forward Unto Dawn.
Halo 2 Anniversary - Cinematic Launch Trailer
Here is the cinematic launch trailer for Halo 2 Anniversary, featuring CG by Blur Studio.
Axis Animation Behind the Scenes of Halo 4: Spartan Ops
Axis Animation go behind the scenes on their amazing Halo 4: Spartan Ops CG cinematics.
Making Halo 4 - Part 1 and 2
Join 343 Industries on a 20 minute behind the scenes featurette on the creation of Halo 4.