Valve had me at first person, four player co-op, zombie survival horror. “Left 4 Dead” comes out next week and I’m excited; more excited after I played it.

The demo had the first two stages of the first chapter and it’s fun as hell. “Left 4 Dead” shows the depth and polish that Valve is known for.

The visuals of the game are great. The world has a post-infection “28 Days Later” feel that throws you right into the head exploding carnage. Turned over big rigs, containment fences, streets littered with biohazard bags, it’s all there.

One thing that made the game real was the flashlight – wow, a flashlight…nifty I know. The beam stops about 20 feet in front of you. Keeping you guessing what’s just beyond your vision. The worst – and by worst, I mean best – part is the flashlight is attached to the barrel of your gun. Anytime you reload you lose your vision. This really sucks when your ass is swarmed and your getting the tar kicked out of you.

The inability to see coupled with eerie music with the soft, distant weeping of a witch zombie laying in wait somewhere in the area had me thinking more than once, “Oh shit, what the fuck, that a witch or a pile of rocks? Fuck I don’t know. Fuck it’s a pile of rocks… damn I’m such a pussy.”

The sound in horror is what gets the heart going; L4D is no different. I constantly had my ear to the ground waiting for the howl of a hunter. Wondering when, and who, the hooded bastard was going to spear to the ground.

A down fall is that the A.I. is touch and go. The first part of the demo has the survivors stranded on top of an apartment building, needing to work down to the street and into the subway. In the apartment building the Infected A.I. seems weak. I could walk into a room and wave my flashlight in the air like a crack addict and they would stand there, facing the corner and scratching their ass.

If this is a flaw, it’s overshadowed when the infected rush you. When they get going, the intensity is kicked to high and you’ll be glad you’re not alone.

If you don’t have four people in the lobby when you start that’s fine. The stand-in buddy A.I. is good enough to not get you killed and keep you alive.

Piece of advice, find and keep four people. The game expects you to work together and if you wander off, the game will punish you and your team for it. This is definitely the case when you run into boss zombies. Each requires a different tactic for you and your merry band of misfits to figure out.

Left 4 Dead constantly has you walk the knife-edge between complete disaster and barely surviving; making one play through feel different, yet vaguely familiar, from the last.