"Halo 3'' comes to stores Tuesday with some pretty big shoes to fill -- namely those of "Halo'' and "Halo 2.''

The good news is the long-awaited Xbox 360 title largely delivers. "Halo 3'' is slick to look at and terrific fun to play, building on the success of the hit franchise.

The storyline in the single-player game is as convoluted as ever. Microsoft has asked reviewers not to disclose more than a dozen elements of the plot.

Suffice to say, the alien Covenant has invaded Earth, where a huge artefact has been discovered in Africa. Master Chief is trying to save the planet.

You are on the move from the get-go. The pace of the single-player game is rapid and the enemy is everywhere, as befitting humanity's last stand.

Bungie Studios has clearly looked long and hard at what worked in the first two games _ and added to it. Like the use of vehicles, for example. "Halo'' has led the way in smooth and easy vehicle play, and the developers have cranked it up a notch this time.

The new Hornet is a blast to fly. The Mongoose and Prowler add to the ground game. And the popular Scorpion tank is as fun to drive and shoot as ever.

The game's artificial intelligence has also improved. Jump into the back of a Warthog to man the gun and a soldier will jump in behind the wheel. He may not drive as well as you do, but he gets the job done while you fire away.

There are also new weapons. The Spartan Laser packs a huge punch, but takes a while to warm up. If you hit something with it, it's done, but you run the chance of being picked off while waiting for the weapon to kick in.

You will find yourself changing weapons throughout the game. Ammunition does not seem so readily available at times, forcing you to discard one weapon to pick up another. There are choices in weapon pickup and they carry consequences.

Power often comes at the expense of ammunition. A big gun carries few bullets but if you come up against something like the Covenant Wraith tank, you will need something with a kick. Coming up against a giant Scarab also requires some thinking _ on the run.

Sticky grenades, power shields and drains, as well as other gadgets, add to the exotics available in the game.

Using the melee function with your weapon also works well at times. Dual-wielding weapons, a big part of "Halo 2,'' do not seem as efficient this time around.

The game is also smartly planned with developer Bungie Studios laying out a road that expands as the adventure progresses. While you are running and gunning for most of the game, there are moments to sit back and enjoy as it progresses _ notably via some rich cutscenes.

Some sequences almost seem to be a homage to those in the earlier games.

While there were a couple of spots that had me stumped for a while figuring out where to go next, the game usually leads you in the right direction when you get stuck. And for the most part, the gameplay is seamless, pulling you along for long stretches of time.

Gamers will no doubt debate the ending. presuming they get to it. But in a futuristic world bristling with technology, there is a decidedly old-fashioned feel to it. Good on Bungie for that.

The legacy of "Halo 3'' will more likely be the multiplayer portion of the game than the single-player campaign. The multiplayer mode was a huge hit in "Halo 2'' and Bungie has made it better this time, with richer maps filled with more toys. The multiplayer editor, called The Forge, also promises to be a huge hit with "Halo'' gamers.

It is the multiplayer mode that will keep the "Halo'' universe alive. The single-player campaign may not last as long, but it is still a compelling journey.