Another trip to Rockstar in London for a controlled preview of its crown jewels, GTA IV. This time we are allowed to direct Niko Bellic around Liberty City, free roaming and then attempting to complete three tough-guy missions. So now we can tell you what to expect in broad terms, but our Rockstar rep was under strict orders not to reveal anything too deep. Tantalising? You bet! Frustrating though when you're a fan. But you take what you can get.

Liberty City is jaw dropping. It looks easily on par with visual benchmarks Gears of War, Resistance and PGR4, but manages to be even more staggering because it is so vast. As Niko kills time on a street corner dusting up some innocent bystander for some cash (this is GTA, it's what you're here for), it's chilling to realise that he is just a speck of dirt on a gigantic map of this filthy city. Which Liberty certainly is, have no doubt about that.

Our demonstration began with Niko on the river in his speed boat, with Broker (Brooklyn) to his right and Algonquin (Manhattan) to his left. The Broker Bridge, in all its finery, appears out of the haze in the distance, Statue of Happiness (Liberty) close by. Liberty City is huge, in every direction you look, as far as the eye can see. We could’ve cruised this river all day to enjoy the view, but like Niko we have work to do. First thing we’re going to do is meet Brucie. Oh boy.

Brucie is among the first in-your-face personalities to make your acquaintance in Liberty. The steroid monkey garage owner is genuinely hilarious, a friend of Niko's cousin Roman who is quite the joker too. It's on Roman's tip that you go to see Brucie – relationships tie everything together in Liberty, and we were surprised at how much we enjoyed the New York style caricatures as they yammered away whenever Niko was within ear shot. Missions, or jobs, are typically handed to Niko in person from a guy who knows a guy who needs a guy to have this or that happen to him. No questions. Sometimes Niko is alerted by his mobile phone, text or call, but we’ll get to that later. Now it's Brucie.

Apparently Brucie is the guy to set you up with a helicopter later in the game, but to begin with he has a 'Search and Delete' mission for Niko – kill a guy named Lyle Rivas. That’s all you're given, which isn't very helpful, but forces you to think laterally as you’ll learn to a great deal of throughout GTAIV. It’s time steal a car; a cop car.

Niko causes a commotion by firing a couple of shots into the air. A cop car screeches to a halt, the cops jump out and Niko jumps in when they’re not looking. Cop cars, you see, have onboard computers that allow Niko to search through files to put faces to names, or even names to faces (you can take snaps on Niko's phone and upload them, how cool is that!). He soon finds Rivas' last known address and activates the siren to get him across town double quick, just in case Rivas knows he's made.

Sadly Rockstar wouldn’t allow us to accept an invite to ‘dinner’, or accompany Roman to a ‘show’. We did, however, join Roman for a drink which led to the pair trying to stagger home blind drunk. Yes, a ‘get home drunk’ mini-game in which the controls are all over the place just like in reality. You’ll be falling around that beer garden a good long while, trust us.

Other things Niko can do with friends: play Pool, go bowling, play darts, go eat. Anytime you want to just hang out, you can. But remember the clock is ticking on more pressing appointments, and you really don’t want to screw things up. So let's see what else happened to folks at the wrong end of Bellic's boom sticks.

One particularly entertaining episode is dubbed 'Truck Hustle' – mafia boss Phil Bell tasks Niko to steal a truck full of ‘cursed brown’ from the Triads. During the inevitable shoot out against all odds in the Triads’ own back yard, you’ll learn how to target body parts such as the arms, legs or head by precision aiming after lock on. You’ll be impressed by the enemies sliding into cover, a la Gears of War, and ‘blind firing’ over walls or whatever else provides convenient cover. You’ll be more impressed if you have a bazooka for Niko to blind fire right back at them.

What happens next is goofy but inspired. The surviving Triads take off in the truck, leaving Niko to give chase on foot and make a dive for the rear bumper, where he clings, Indiana Jones style, for dear life. This movie-style gag continues with another impromptu ‘hang onto the roof for as long as you can without sliding off' mini-game, ending with Niko swinging into the cab and using the driver's own gun to kill him point blank. Job done, Mr Bell is duly pleased.

So far, so unusually overblown and all the better for it. But it’s a low key, incidental aspect of GTAIV we'll mention next. This whole friendship idea extends to more than just doing stuff for names on a contacts list. A good example is the arms dealer Little Jacob. He hitches a ride with Niko en route to a mission called 'Jamaican Heat' – basically a quick shoot out in a back alley. All the while, LJ is chatting to Niko in his strong Jamaican slang, telling Niko what a good guy he is and all that, which makes everything feel really cosy and cool.

There's such a sense of being there in GTAIV. Locations feel like places with a history, and you can tell whether bad stuff is going to happen just by the atmosphere. If the lamp posts are vandalised and there's graffiti on the walls, it's a bad neighbourhood. If the cars are flashy and people have nicely mowed lawns, you’re in a swish part of town – probably Algonquin. Wherever you are, if Niko stops to look around he won’t always need the map to know which district his last car chase out of scanner range has led him. Ambient sounds such as mobile phones or pushers on street corners are subtle clues too.

This really is Grand Theft Auto up close and personal while at the same time being so grandiose that it makes GTA on PS2 and PSP look like toy town. It's grittily realistic, but with unmistakable tongue-in-cheek videogame conventions to keep things light when it could get too dark for comfort. GTAIV is shaping up to be so classy, you’ll want to wax polish your PS3 or Xbox 360 before and after you play.

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