This level is going to begin with a very interesting cut-scene. Be patient, because you won't be given control over Riddick right away. Approach the guard standing in front of you and perform a countermove when he tries to hit you [#320]. Sadly you won't be allowed to collect his gun.
Exit the container and go to your right. Once you've reached a much larger cavern you'll witness a new cut-scene. Treat this scene as a taste of things to come. :-) For the moment all you have to do is to slide down into a large hole in the ground [#321].