There's only one video game that matters next week, and that's Halo 3, Microsoft's futuristic shooter that is expected to boost its Xbox 360 console and be one of the year's top titles.

It's the sequel fans have waited three years for after Halo 2 ended abruptly with the game's hero, Master Chief, arriving in Earth orbit to finish the fight against alien invaders known as the Covenant.

'Halo 3' is going to be a game that nearly everybody gets this year. The demand is very, very high. I don't think that's spin, it just is, said Douglass Perry, editor-in-chief of online video game service GameTap.

But as with any hugely hyped entertainment product there are some who doubt that Halo 3 can live up to expectations.

It's inevitable that someone will be disappointed, but definitely as a package you're getting your money's worth, said Geoff Keighley, host of Spike TV's Game Head show.

I'm amazed at how much is packed on that $60 game disk and think that will be something that surprises people.

In Halo 3 Master Chief tries to stop an extremist faction of the Covenant from activating an array of massive ring-shaped devices scattered through the galaxy.

The rings -- the halos of the game's title -- are ancient alien artifacts that are like interstellar bug exterminators that will scrub the galaxy clean of all life.

Meanwhile, humans and a sympathetic group of Covenant must also stop alien parasites known as The Flood from assimilating everyone else. The Flood were the reason the halos were built in the first place.

It's not overdone, it's handled really seamlessly, Perry said of the story. It makes it a lot more intriguing and definitely more satisfying than 'Halo 2' was.

Part of the attraction of shooter games like Halo is the variety of weapons and vehicles players have at their disposal. Among the new treats in Halo 3 are a flamethrower, a gravity hammer, a steel-wheeled Brute chopper and the massive Elephant military support vehicle.

The Halo games are also known for their highly polished multiplayer modes. While several games allow two people to play a game together, Halo 3 pushes that to four people, something sure to be popular among those who attempt the game on the heroic or legendary difficulty settings.

The second Halo introduced online multiplayer battles and is still seen by many as the gold standard there because of the ease with which players can set up matches, hook up with friends and modify the rules.

Halo 3 goes a step further with its Forge feature that lets players add or remove weapons, vehicles and other items even while a match is in progress. It turns multiplayer areas into giant playgrounds.

Forge is a major feature of the game that hard-core players are going to go absolutely bonkers for. It's a big sandbox of tools that you can go wild with, Perry said.

Halo 3 will go on sale at midnight on Sept. 25. Microsoft executives have said they expect initial sales to top those of Halo 2, which pulled in $125 million in its first 24 hours.

Microsoft hopes the game will spur sales of the Xbox 360 and cement its lead over Sony's PlayStation 3, which has lacked a must-have title to help drive adoption.

This isn't just the biggest game of the year, it's also the capstone on one of the greatest gaming trilogies out there, Keighley said.

I'm sure Tuesday will be day of decreased productivity across the nation because there are going to be millions of people calling in sick.

Microsoft