Once again Shirley delivers the goods in this gripping, superbly characterized screen adaptation of the infamous 1st person shooter game that charmed our socks off over ten years ago. What is it exactly that you want out of a video-game-turned-movie novelization? I personally have less interest in a paint-by-numbers representation carefully shaded in to please fans than I am in simply reading a killer story w/believable characters, and that is exactly the author's approach in this satisfying homage to "shoot first ask questions later" pulp sci-fi horror.
It's a shame some folks don't seem to appreciate the simple literary approach of a rip roarin yarn the author has woven here, because if you can check your baggage at the door, you are in for one hell of an intensifying reading experience. This book is the literary equivalent of a sure-shot, one-clip barrage from a BFG emptied into the reader till he's effectively been rendered into so much pulped swiss cheese. I.e, it is best experienced in one sitting (if possible for a great part of its target audience, notoriously short of attention span), because it works like a pot of cold water put on a burner set on high: by the time you get to the last 10 percent, the narrative is boiling over with such fury the reader almost has to hold their breath to get through it all.
It is a sustained symphony of violence so adeptly handled by the author, that when the reader reaches the crescendo it is all one can do to refrain from tearing the pages out as you turn them. This is straight up pulp fiction at its finest, it transports the reader to another world of unbelievable horrors and action in a stylistic manner which renders the whole experience a sustained sense of realism, and that is all one could ask for in a narrative such as this.