Tucked away in a secluded bungalow in West Hollywood's Château Marmont, a hotel as famous for those who stay there as it is infamous for those who have died there, a world reimagined comes into focus.

Standing hands akimbo, a nonplussed expression planted firmly on his almost cel-shaded face, Niko Bellic could easily be a touched-up still. But it's no bullshot. The world around Bellic is bustling with activity: Bits of trash float on a digital drift of wind, people walk by, cars cruise in and out of the shot, an almost familiar skyline fills the hazy background. A palette of city sounds laid over this living diorama completes the effect.

"We decided we wanted to go back to the basics and reimagine the world," Jeronimo Barrera, Rockstar Games Vice President of Product Development, says. "The results have been incredible."

Grand Theft Auto IV is, its creators tell me, the biggest leap forward in experiential sandbox gaming to ever come to the franchise, larger even than the one that brought the once 2D top-down series into the third dimension.

"In many ways it's a bigger leap going from San Andreas to GTA IV than it was going from 2D to 3D," Barrera says.

That shift isn't delivered in one mighty leap, he adds, but rather in a collection of tweaks and changes made to the basic nature of the franchise.

"It was about hitting reset and reworking a bunch of things," he said. " We reworked everything from locomotion to targeting."

Bellic is on the street, a local tough has asked him to kill off a guy who's about to talk to police. Instead of telling him where the guy is, he suggests Bellic get his hands on a cop car and use the laptop to find out where he usually hangs out.

Bellic calls 911 on his cell phone and then when the cop car arrives, he carjacks it and drives away. In this latest GTA your wanted level corresponds to the place in which you commit the crime. As soon as you break the law a shaded circle pops up on your radar showing you where police are looking for you. If you can get out of that area before your spotted you can lose the cops and, eventually, your notoriety.

Bellic tears around the corner and drives to an area where he can pull over. When he taps into the cop car's computer a screen comes with tons of options including one to search for suspects either by name or photo. Using a pop-up QWERTY keyboard, he taps in the name and gets an address to go to which is added to the car's in-board GPS.

When Bellic tracks the guy down he runs, kicking off a car chase. The drive through town doesn't look or feel like a scripted event, and a Rockstar employee is in full control of Bellic and his stolen car, but some of the things that happen, like a large truck dumping its load of barrels onto the street, were written about by other publications which saw the game as well. I suspect that there might be a number of events like this which can be automatically triggered depending on where you are and what's happening.

After zipping through the rolling barrels, Bellic catches up with his quarry, whose car is marked with a red arrow, on a bridge and manages to fire off enough shots to first flatten the suspect's tires and then set the engine compartment on fire. The car, riding on rims now, tries to zip between two cars and misses the gap, fishtailing into a vehicle before rolling. The bad guy is thrown from the car, sliding across the bridge to stop near the railing, and then the car explodes, catapulting the would-be informant up and off the bridge.

The Rockstar guys erupt into laughter. "Did he just go off the bridge?" one asks, laughing.

The mission's complete, but Bellic still needs to get off the bridge and two cop cars are speeding toward him from the other side. He zips past them and comes to a stop. Getting out of the car, he pulls out a rocket launcher, which slides out of his pocket like a gag from a Bugs Bunny cartoon, and fires a shot off at the police cars blowing both up. Instantly, Bellic's wanted level is raised to three stars and the cacophony of an approaching army of police can be heard in the distance.

"You're three stars? How'd you get three stars?" Barrera asks of the demo player. "Oh you blew up those cop cars."

"You told me to."

The sound's getting louder.

Bellic hops back into his car and makes his way toward the other side of the bridge, as he approaches we can see that it's been blocked by police and not just police cars, but what looks to be police humvees. Bellic rams his way through and tears down into a tunnel. He makes it up through the other side as police follow in hot pursuit, guns firing. The car, now on its rims and engine smoking, rolls slowly into a gas station.

"Oh, a gas station," someone in the room says.

There is, it seems, a moment of breathless anticipation as Bellic jumps from the car and runs past rows of gas pumps. He turns to see dozens of police cars descending on his still smoking car. And then the world explodes, the image on the screen literally blurs as the car, the gas station and all of the police cars near it turn into a blooming fireball.

Bellic turns and runs down a grass hill to another highway, but two police cars are already descending on him. Above a helicopter is following. He pulls out that rocket launcher from his pocket, looks up at the sky and fires off a shot at the copter. It's hit, smoke billows from its engine, it starts to spiral, dropping suddenly to the ground about 100 feet from Bellic and explodes.

An alert pops up on the screen "ONE MAN ARMY ACHIEVEMENT UNLOCKED" before the demo player quickly gets rid of it and uses a cheat to rid himself of his escalating wanted level.

While the setting for this latest Grand Theft, based on Manhattan and its surrounds, isn't as large as San Andreas in terms of land mass, it's more detailed and there's more to do, the Rockstar guys tell me. You can drive boats, helicopters, motorcycles, cars, trucks, hail cabs, but you can't fly a plane.

"It's not like people in New York fly airplanes around, it's more of a helicopter town," Barrera says.

The games intertwined storyline takes place over a number of months in the city with two minutes of gameplay translating to an hour in the game world.

The game now incorporates auto-saving to make it a bit more player friendly this time around. After every mission the game saves.

"It makes it more accessible," Barrera says, "gamers shouldn't have to fight against the save system to enjoy a game."

Other neat tweaks include a cinematic mode which slows time to a crawl on the fly and can be used at anytime in the game, making it easier to do things like slip through rush hour traffic at high speeds, cab rides which can either be enjoyed from beginning to end or, for a small fee, skipped entirely. You can also bribe the cabbie to break traffic laws to get you to your destination faster.

The game's once tragically flawed targeting system has also been heavily reworked. I got a good look at the system in a mission that involved Bellic having to take out a bunch of mobsters from a construction site.

The mission starts with Bellic sniping three guards from atop a nearby high rise. The demo player takes out the first two guards with headshots. The first man toppling from his position high atop the construction site, tumbling end-over-end until he lands with a thud on the ground below, his rifle popping out of his dead hands and letting off a single shot.

The third man is taken out with a shot to the leg. As he falls to the ground, he appears to weakly flail. The man's body finally crashes into the roof of the car, crushing it flat.

Once Bellic clears the guards he makes his way across the street. The demo player, hurrying to get into the heart of the mission, lets a car clip Bellic, who falls to the ground. Getting up slowly, Bellic plants his hands in front of him, gets to his knees and then slowly stands, a nice touch.

Once in the construction site is cleared, Bellic moves into the yard and almost immediately has to duck for cover, a new addition to the game's fighting system that allows you to stick to cover like you can in games like Drake's Fortune or Gears of War.

Once in cover, Bellic can fire blindly from his hiding spot or lock onto a target and plug away at them. You can also now free fire in the game.

"It's comparable to a shooter," Barrera said.

A target's health is shown in the targeting reticule when you lock-on, while Bellic's appears in a green bar that wraps around the radar. A blue bar shows his armor, like a bullet proof vest. As Bellic's adversaries die the items they drop glow in the dark showing where to find ammo, weapons and cash. And when Bellic finally, inevitably, dies in the heat of battle the world fades to black and white.

The game will, Rockstar has said, feature multiplayer, but they're not quite ready to talk details on what that will entail. They did tell me that there won't be cooperative multiplayer because it wouldn't really fit in with the game's story.

'There's really only one main character, so it wouldn't fit," Barrera said.

As with most of Rockstar's games there are definite cultural themes at play in Grand Theft Auto IV, though in this game it might not be as easily definable as the gang culture of San Andreas or school culture of Bully.

"There is an immigrant theme, a world culture theme," Barrera says. "This is Rockstar's ten year anniversary and when we got started we all moved to New York at the same time, so there's a lot of that in there.

"The beauty of our games is that we don't hire a research firm to figure out what we should be making games about."

Instead they make it about the things that interest them, and it it shows.