While in Australia, Hallowe'en is over for another year, it's still October 31st in the US, and to mark the spooky celebration, Valve have released not one, but two videos for their upcoming zombie-hunter, Left 4 Dead.

First off, we have a TV Spot, which is probably a good place to start if you're not sure what all this carry-on is about.

The ingame content used in the TV spot is taken from the opening sequence of the game - if you like what you see, we've got the whole Intro Movie for you to check out, more than four minutes of footage lifted straight from the game!

Download the Left 4 Dead Intro Movie

This promotion is part of a US$10 million marketing campaign for the upcoming title, featuring two television commercials which will air on both network and cable television in the US. We're getting a sneaky peek - the first spot hits the airwaves on November 8th.

Coming very, very soon for both PC and Xbox 360, Left 4 Dead follows the lives of four armed survivors in a world overrun with zombies. The only way out is to fight through the outbreak, working together to finish each stage, sharing ammunition and weapons, helping each other out and rescuing teammates when the zombies attack.

As if that wasn't intriguing enough, you don't have to play as humans. Another four players can step into the shambling shoes of assaulting zombies, whose aim is to take down the other players. There are also four mutant 'boss' zombies thrown into the mix, complete with unique powers that can devastate the human survivor attack.

The game aims to do for co-op gaming what Counter-Strike did for team combat, with zombies thrown in as a bonus. Can't complain really, can you?