Halo: Reach launches on Tuesday with a gripping story about a last-ditch effort to save humanity in the face of an alien invasion. It is the first major launch of the fall game season, but it may arguably be the only one that could save the video game business — at least in terms of its sales performance in 2010.

Stores across the country will open at midnight Monday night to sell Halo: Reach, which is the last installment of the game that will be created by Bungie, the game’s developer since the first game, Halo: Combat Evolved, debuted in 2001. Previous versions of the game have sold more than 30 million units, generating $1.9 billion at retail and creating a cultural phenomenon that cemented Microsoft’s place in the video game business.

But console video games have been weak all year, with sales down 8 percent year to date, according to market researcher NPD Group. The recession has weakened gamer enthusiasm for new titles. Used games are eating away at the sales of $60 new games. And swarms of free games — on everything from Facebook to the iPhone — are stealing time away from the games played in the living room.

But starting with Halo: Reach, the video game industry is making its bid for a comeback. Then, the drumbeat of new game launches will continue on through the holidays.

Activision Blizzard is readying the launch of Call of Duty: Black Ops, another series in the combat game that last year became the best-selling game of all time. Electronic Arts will challenge that title’s hegemony with Medal of Honor. Sony will launch Gran Turismo 5, the latest in its racing game franchise, and Disney will launch Disney Epic Mickey for the Wii. Ubisoft has titles such as Assassin’s Creed: Brotherhood and Ruse; Take-Two Interactive has Sid Meier’s Civilization V on the PC and Blizzard will soon be releasing World of Warcraft: Cataclysm. Of those games, Activision Blizzard claims that Call of Duty: Black Ops will be a sure-fire blockbuster, possibly eclipsing the Call of Duty: Modern Warfare 2 title from 2009.

It’s also going to be a full-scale blitz for new hardware. On Sept. 19, Sony will begin selling its wand-like Sony Move motion-control system. In November, Microsoft will launch Kinect, a 3D motion-detection system that will get gamers off the couch in the same way that the Wii has done. Nintendo is planning to launch the 3DS handheld, which can show stereoscopic 3D images without the need for glasses. But it’s likely that game system will begin sales next year.

The video game industry has the opportunity to prove that its hardcore business is still full of life and that snack-sized games played on the iPhone or Facebook are not its future. If it can’t post sales gains this fall, then the slide toward free-to-play online or mobile games may become inevitable. So there is a lot at stake this season.

And it is appropriate that Halo: Reach is the game that starts this new avalanche of titles. Gamers look to Halo for innovation in game play and storytelling. To date, fans have logged more than 2 billion hours playing Halo games on Xbox Live. The last major release was Halo 3 in 2007. A year ago, Microsoft released Halo 3: ODST, which was a short snack of a game meant as an appetizer for those awaiting the next big game.

The sales should be strong, but it’s unclear what effect that piracy of the game will have, as hackers obtained a copy of the full game more than a month ago.

So far, the average review score for Halo: Reach is 94 out of 100 on Metacritic, which aggregates review scores. Of 30 reviews posted so far, 12 have been perfect 100s. I previewed the game in final form at a press event. But now I’ve been playing the finished game for a couple of nights, getting through about two of the nine major segments of the single-player campaign. So far, so good. Playing the game on “Heroic” level, or one notch above normal, is appropriate for players like me who have played all of the four major first-person shooter titles that preceded this one.

It’s not easy to get through the missions, which so far focus on team combat, nighttime stealth, and riding around as a gunner in a Warthog, or a dune buggy with a big gun mounted on its back. As I noted in an earlier preview, Halo: Reach will deliver very familiar game play for fans with some tweaks that make the combat more interesting. I approve of what I’ve seen so far, but I won’t publish a full review until I’m done playing.

The sixth game in the series (after Halo, Halo 2, Halo 3, Halo 3: ODST, and Halo Wars) is a prequel to the events in the original Halo. It is set during 2552 in the midst of humanity’s long war against the collective of alien races known as the Covenant. At this point, most of humanity’s interstellar colonies have fallen, and Reach is one of the last, besides Earth.

In the game, you are part of an elite team of six Spartan super-soldiers, each of them akin to a Master Chief (the original hero in Halo) but with different specialties such as sniping, big guns, or the trusty assault rifle. You can play as a male or female. There are plenty of cinematics in the opening section, much like any Halo game, where you can get a feel for the situation and the capabilities of the team.

The landscape looks pretty, with lots of far-reaching views. The enemies in the game are still fairly unpredictable, dodging one way or another, sometimes rushing you, sometimes ducking for cover. But in Reach, you have the chance of fighting in groups of super-soldiers. You can also fight alongside lesser UNSC soldiers, who are more like cannon fodder. That changes the play in a good way. I’m looking forward to finishing the game and playing on multiplayer. I’ll report back for full review duty later.

Meanwhile, check out the video of Halo: Reach game play below.