"So, you like racing games." That's generally the first thing most new guests say the first time they enter my media room and spy the Sparco GT Racing Cockpit tucked behind my theater seating. I love the looks on their faces when I answer, quite truthfully, "I cannot stand the things. The cockpit is for Gran Turismo and Gran Turismo alone. And don't you dare call it a 'racing game'."

The term "racing game" carries with it certain connotations: instant accessibility; a broad selection of hop-in-and-drive sports cars; slick, press-of-a-button power slides; an emphasis on winning at any cost. Gran Turismo is none of those things. Since its debut ten years on the original PlayStation, the series has made its mark by pushing the boundaries of brutal realism as far as current gaming hardware would take it. Every generation of new PlayStation hardware brings with it a new generation of bigger, badder Gran Turismo games, with more detailed cars, better physics, more lifelike sound, and better AI. And although the first full GT release in the HD generation is still a year away, Polyphony's latest teaser—Gran Turismo 5 Prologue—demonstrates that the ante has been upped yet again.

For the uninitiated, perhaps a bit of explanation is in order. As its name implies, Gran Turismo 5 Prologue is not intended to be seen as a full-fledged game release. Nor, on the other hand, is it a mere tech demo like Gran Turismo HD Concept. Think of it as something sort of halfway between a game demo and full release—a weird, scaled-down, $40 state-of-the-game palate-whetter intended to keep raving fans of the notoriously behind-schedule series sated until the perfectionists at Polyphony are ready to reveal their final work to the world. It boasts six tracks (twelve layouts total), nearly 80 cars (a pittance compared to a full GT release, but a wonderful selection compared to most racing games), single-player Arcade and Event modes, and sixteen-player online racing. Other online features include GT-TV, a nifty high-definition video-on-demand service focused on real-life racing content and Gran Turismo-related movies.

It also boasts a level of graphical muscle sure to elicit reactions forbidden by the Old Testament and generally frowned upon in polite company. The verisimilitude of the car models is downright disturbing at times. Quite frankly, I'm not sure the human brain is entirely ready to take complete control of images this lifelike—especially the down-to-the-tach-needle perfection of the in-car dashboard renderings. The tracks are also recreated with such detail that imperfections in the paint striping and divots in the asphalt are apparent. And if the backgrounds don't quite measure up to the resplendence of the virtual vehicles and raceways—power poles and other small, far-off details can get a bit stair-steppy at times, demonstrating the fact that not even 1920x1080 resolution is enough to capture every minute detail of Polyphony's immaculately conceived world—take solace in the fact that it'll all be whizzing by so fast at a blistering (and rock-solid) 60 frames per second that you probably won't have time to notice. The new graphics engine's dynamic lighting also goes a long way toward glossing over any piddly rendering imperfections—come screaming out of long tunnel into the bright sunlight, and you'd better be prepared for a few seconds of blindness as your virtual eyes adjust. It's just one little layer of icing on an already nummy cake.

Lest you think that the focus is all on the eye-candy, Gran Turismo 5 Prologue also boasts some of the most raucous, foundation-rumbling, picture-tilting audio of any video game. Ever. The game's audio setup menus allow you to select from three levels of dynamic range: normal, small home theater, and large home theater. If at all possible, select the latter. The meticulously mimicked engine noises blend together from every direction to create the sort of aural pornography that car aficionados dream about.

My wife, reading over my shoulder, notices that I'm writing about the sound and reminds me to mention the music. "There's music?" I ask. "Yeah, and it sounded pretty darn good to me," she says. So apparently there's music. But as I was saying, the car noises are simply above and beyond anything yet attempted in a video game. Its 7.1 channels of hard-driving engine sounds are so authentic, you can almost tell by listening alone when your car needs an oil change.

Speaking of which, as one might expect given that this is a mere preview of the final game, the series' legendary Gran Turismo mode isn't included here. And given that this is the real draw for most GT fans, its absence leaves a great big gaping hole right in the middle of the game that's impossible to ignore. This means that while you can shop for new cars to your heart's content, and even tweak them a little after winning all of the game's racing events, you can forget spending hours shopping for new exhaust systems, running races over and over again just to make enough money for a new braking system and tires. Forget boring out naturally aspirated engines or upgrading turbos. It would be ridiculous to expect Polyphony to include such an extensive career mode in a demo—even a $40 demo—but without it, Prologue feels less like a scaled-down GT game and teensy bit more like a Gran Turismo-ized... ahem... racing game.

It's also far past time for the series to incorporate car damage, given the ongoing emphasis on realistic physics. At times, the other cars don't feel like opponents so much as the sort of cushy gutter bumpers you need to get through a drunken round of midnight laser-light bowling. And guard rails still make a handy substitute for deft braking in a pinch. That's pretty hard to forgive, given how amazing the physics are otherwise. The good news is that Polyphony has promised to add car damage to Prologue by the end of the year via a patch. The bad news is that as of now, the artificial intelligence of the computer racers isn't quite ready for such an addition. Computer opponents tend to stick to their lines whether you're there or not. Imagine the frustration of getting knocked out of second place by a brain-dead automaton doggedly sticking to its pre-programmed course. Rubbing is racing, sure, but unintentional rubbing isn't a competitive tactic; it's just bad subway etiquette. Hopefully Polyphony feeds the virtual racers some brain food before unleashing bodily harm upon us later this year.

If this sounds like a conflicted review, that's because I can't entirely make up my mind what grade I would give Gran Turismo 5 Prologue if we were the sort of publication that attached numbers to things. On the one hand, it's newGran Turismo, and that's never a bad thing. The graphics and sound are incomparable, despite minor imperfections, and the controls are magically delicious, whether you're using a stock SIXAXIS PS3 controller, the new DualShock 3, or one of the compatible Logitech force-feedback steering wheels. Better than any game before it, Prologue captures the edge-of-your-seat, nigh-chaotic tension of actually slinging a few tons of steel around a long stretch of asphalt, barely hanging onto some semblance of control with the tips of your fingernails, certain that a butterfly flapping its wings in Beijing could send you into a spinning, bone-crunching crash. And whereas a win in other racing titles might elicit a hoot or holler, a gold cup here would have even Brooke Shields reaching for a pack of Camel Filters. Not that winning is that hard, mind you; it just feels that good.

The real question, though, is this: is Gran Turismo 5 Prologue worth the asking price of $40? Mind you, it offers more and better gameplay than many full-price games, but without Gran Turismo mode it barely hints at what Gran Turismo 5 will eventually be, and honestly I can't see it keeping me glued to my screen for the next year, the way Gran Turismo 4 did. But in the end, yes, it's worth all 4000 pennies to this racing junky, because much of what I've picked on here amounts to little more than nits. Besides, let's be honest with ourselves here: nothing else is even going to come close to the real thing until it takes the gaming world by storm next year. And if you're looking for an inventive way to show off your home theater, you'd have to look long and hard to find anything much better than this.