Half-Life 2: Episode One is the first in a new trilogy of episodes that are scheduled to be released over the course of the next year. The first episode fills in a lot of the story gaps that you may have found with Half-Life 2 and at the same time opens up a whole new world of possibilities. You quickly learn exactly what is going on and why events of Half-Life 2 were taking place although all the questions posed are still not answered and the G-Man will still be just as much a mystery for many Episodes to come. Let's hope that Episode 2 actually starts to answer questions about what the hell is going on!

Episode One starts off exactly where Half-Life 2 ended - as Gordon and ally Alyx Vance were caught in a massive explosion. Now, you (as Gordon) are uncovered from a pile of rubble and debris by Dog /Yes, that loveable mechanical beast is back :-D/ and Alyx. Your main goal is to get out of City 17, but events that take place during your escape sidetrack you and Alyx a bit. With the Citadel reactor on overload, it's a battle to escape the ruins of the gutted Citadel and the city itself. Of course, that's easier said than done!

Episode One plays quite differently from Half-Life 2 in the sense that it's a single player cooperative game with Alyx - throughout most of the episode, you and Alyx will team together to solve puzzles, cover each other, and take on waves of enemies. Alyx is capable assistant and she's often the difference between victory and defeat in many encounters, as she'll cover your back while you're busy trying to sort out the puzzles. She'll even prompt you to danger allowing you to escape just in time which really adds to the feel and suspense of the moment. I must admit that Alyx's AI is superb, I never found myself frustrated because her. Her reactions to events in the story, like the train crash, really made her seem much more human. She added to the game immensely. She also provides good narration that progresses the storyline, and some laughs as well. My only problem with Alyx is her smile. It just looks so fake to me.

Just like the original Half-Life 2, the Episode One keeps you entertained almost the entire time through perfect pacing and a rich atmosphere. The levels are well done and the environments are great too (although the environments of the Citadel and City 17 were already explored in Half-Life 2). Episode One also brings some interesting puzzle elements, and may actually require you to get your brain kick started occasionally. The puzzles are fun and not too hard to have to repeat if you do mess up. For example, there are bridges you need to activate by throwing energy balls at certain devices, etc. The puzzle took me about six or seven deaths to really figure out, but it was even fun to die.

If there's one thing Episode One does even better than Half-Life 2, it's the scare factor. The dehumanized workers that lurked in the Citadel play a larger role this time around, and are almost guaranteed to freak you out completely in one scene. The claustrophobic dark level, Lowlife, has you desperately avoiding running out of battery for your flashlight and sweeping the area constantly to try and see those zombies creeping up on your flanks. Also, a new enemy is added to the mix, a "Zombine" which is a combine soldier that has been turned into a zombie by a headcrab. This headcrab on a Combine body is a little like a cross between the bomb-headed kamikazes from Serious Sam and a walking tank. They really spice up the action too due to their kamikaze strategy of randomly pulling out a grenade and running at you. Fortunately, it's nothing the gravity gun can't solve.

The action in the game is a lot more intense than the original. While Half-Life 2 would toss several Combine at you, then some headcrabs, then some more Combine, Episode One will have you entering into the middle of already massive brawls between Combine and Headcrabs, then have both turn and start attacking you, making the fights feel a bit like a free-for-all. It's very interesting to see Zombines tearing through their former squadmates, overpowering Combine troops with their fierce melee attacks.

The Half-Life 2 arsenal is available in Episode One entirely unchanged. The only notable addition is Alyx's side-arm that she uses through most of the game, and unfortunately can't be used by the player. What this says about the Half-Life 2 weaponry is that it was and still is exceptionally well-rounded, and the addition of another gun might have seemed unnecessary. However, those of you hoping to be tossing people around with the gravity gun as you did near the end of Half-Life 2, will be disappointed. The developers do tease you with the ability, though, but the fun is over quickly :)

One of the most unique features in Episode One is the addition of developer commentary, which, once enabled, can be accessed via chat bubbles sprinkled throughout the game. The commentary has the developers mainly offering insights about design decisions that influenced sections of the game. Besides the single-player content, Episode One comes with a Source port of Half-Life deathmatch. Yep, all the original fun ported over from the Quake engine to Source. Don't expect any huge visual upgrades though, but the water and some of the textures were touched up a bit. You will also get the Half-Life 2 Deathmatch.

Overall, Half-Life 2 Episode One is a solid game, but it was a little too short for me. I played it on regular difficulty and it took me less then 4 hours at normal difficulty. Sure, it costs only about 20 bucks, but I still feel like I should have gotten at least a few more hours of gameplay. There is also little replay value, so it hurts this even more. So, if you want to play some more of Half-Life 2 gameplay I would recommend this but only if you are willing to buy it for that price. In my opinion, 10 bucks would be a more appropriate price for this game, that's why I gave it a bit "lower" score.

Note: Episode Two is currently scheduled for the end of 2006.

System requrements: (You don't need to own Half-Life 2 to play Episode One, as it's a stand-alone product).

Minimum: 1.2 GHz Processor, 256 MB RAM, internet connection, DirectX 7 graphics card
Recommended: 2.4 GHz Processor, 512 MB RAM, DirectX 9 level graphics card