There were moments during out gargantuan hands-on with open world blow-em-up Just Cause 2 when our eyes almost popped out of our head. The sheer ridiculousness of what you can do in the fictional South East Asian island of Panau - intentionally and, often, unintentionally - is so far off the destruction scale that it's broken through the upper atmosphere and finished up somewhere in space. This, funnily enough, is just about the only place you can't go in the game.

It has, of course, got everything you'd want from an over-the-top sandbox game. It's got explosions - lots of explosions - choppers, jets, and cars to jack, people to kill, three factions to work for, and a massive game world - 1000 square km to be precise. But what it's got that no other over-the-top sandbox game has - indeed no other sandbox game of any kind, well, apart from the first Just Cause - is a kick arse grappling hook (yes, we know Mercenaries 2 had one, but it wasn't very good). In fact, Just Cause 2's grappling hook is the best video game grappling hook of all time.

It's really that good. More than any weapon in any video game we've played in the last 12 months, Just Cause 2's grappling hook is designed to enable chaos. It does the bog standard stuff, like attach to pretty much any surface, and pulls you forward at breakneck speed. But it also does the... er... non-bog-standard stuff, which we're about to spend the next several paragraphs explaining.

Example one: During the second mission, Latin protagonist Rico "surfs" Swedish alcoholic Blaine's banger as he speeds away from hot in pursuit government soldiers. There are enemy Jeeps on our tail, riddling our flesh with bullets. What do we do? We wait till we cross a bridge, land the grappling hook in the bonnet of one of the Jeeps, keep the LB button (on the 360, the version tested) held down, then release it with the targeting reticule on the tarmac just ahead of the Jeep, tethering it to the road. You know those bits in Hollywood blockbusters where cars flip forward and high into the air? Yeah, well, that happens, except the Jeep in question flips forward and high into the air and over the bridge. Cue screams and our eyes popping out of our head.

Example two: During one of the many "Faction Missions", we're under the cosh. There are scores of bad guys baying for blood. One of the buggers has a grenade - he's an explosives expert, and harder to kill than the others. What do we do? We land the grapple hook in the git's chest. He throws a grenade. Somehow - and this is purely accidental, although we'd love to say it's down to pure skill - we manage to tether the grenade spammer to his own grenade. He flies forward, landing face first right next to the small explosive device. We run for cover. Boom! Cue spraying blood and our eyes popping out of our head.

Enemy choppers are opportunities - grapple them and make Panau your plaything.

Example three: We're having fun in an armoured personnel carrier blowing everything and anything that offers up "Chaos Points" - the currency that opens up new Agency and Faction missions - during a "Stronghold mission", when our "Heat" (Just Cause 2's take on GTA4's wanted system) gets too hot to handle, and the government soldiers call in air support. Basically, that means fun time's over. The chopper arrives and riddles us with bullets. If we stay holed up in the APC, soon enough it'll blow, and we'll die a horrible, burning death. What do we do? We jump out, look up, and land the grappling hook on the cockpit of the chopper. We fly high into the sky, landing our feet on the glass. Press Y to enter; we enter, successfully completing a quick time event that sees us chuck out the pilot and his crony, Terminator 2 style. Now we're in the chopper; hold the right trigger to ascend, left trigger to descend. RB and LB fires a mini-gun. Panau is now our bitch, and this gunship is our whip. Cue ten explosions in 20 seconds and our eyes popping out of our head.

Example four: We're on another "Faction Mission" - most of the early hours of play are spent earning enough Chaos points to trigger the next Agency mission. This time we're descending a great big hole in the ground with the intention of blowing up the tower that's inside. We go down, shooting, grappling, killing... the normal stuff. We interact with the tower console - a quick QTE - and success. Now, it's going to blow. We need to get out of there quick. We look up - it's going to take too long to grapple our way to the top. What do we do? Gas canisters - every game has them - are propped up against a wall. We grapple one, landing feet first on the "nose" of the cylinder. Then, we land a single bullet. As the gas escapes, we brace ourselves. Boom! The canister fires up into the air like a rocket heading into space, and we're riding it like a heavily-armed space monkey. We reach the top, leap off the canister, fire the grapple hook into the nearest wall, and feel the tower explode behind our back. Cue fist pumping and our eyes popping out of our head.

The grapple hook can be used in so many ways - tethering vehicles to choppers is just one of them.

What do these examples prove? Throughout the game, characters often liken the island to a toy, one that can be played with in whatever way you want. This isn't far from the truth. In many ways it's like Traveller's Tales' LEGO games. In those games, the little LEGO people and the world they inhabit want to be blown to bits. That's what they're there for. That's what they exist for. They want you to do it. Don't worry about their feelings: it's all part of the fun.

And so it is with Just Cause 2. Innocent villages are there to be toyed with. Their homes have been created to be destroyed. It's morbid, but hanging an innocent villager from a tree is exactly the kind of messed up thing the game is designed to allow you to do. Don't feel bad. They want you to do it.

We've played Just Cause 2 for four hours, and we've only scratched the surface. That, of course, is the way it should be - this is an open world game after all. But there are things we can already say with confidence, and one of them is that Just Cause 2 will be a better game than Just Cause. Here's why.

One) It looks better. Not just better, but loads better. The draw distance really is stunning, and it's all rendered in real-time. At the beginning of the game, when you land on Panau at night in pursuit of lost computer files, hundreds of little lights glow in the distance - the lights of houses, flats and apartments in Panau's capital city and its three districts, and even the lights of villages. Each and every light is rendered in real time. If we fancy it, we can go there and see them up close for ourselves.

Closer up, Just Cause 2 is no slouch. Explosions look, and feel, meaty. When loads of things blow up all at once, you feel as if the Earth's crust may very well crack open. All the destruction is persistent, too, so if you wreak havoc in an area, the game will remember it, and it'll even show up in cutscenes. The many vehicles, from Tuk-Tuks to luggage-filled buses, from Nissan rip-offs to sports cars, look at least on par with GTA4's motors, and handle well. Only the character models, and their faces, disappoint.

Just Cause 2 is one of our most anticipated games of 2010. We can't wait.

Two) There's more to do. Just Cause was good, but it had problems, and chief among them was the distinct lack of stuff to do. Sure, it was one hell of an impressive feat - and stood out as an early 360 title - but while its open world was massive, it wasn't particularly interesting. Panau isn't just interesting, it's relentless.

There are, as with all video games, potential pitfalls. Will the grapple hook sustain the game over the course of its 20-something hours of gameplay? Will the early thrills turn to gimmicks? As with so many third-person open world games, the sheer act of shooting a gun - like GTA4, Just Cause 2 uses an auto targeting system - isn't that great. For the first four or five hours or so, it doesn't matter, because the grapple hook is so much fun to experiment with. But after that? With the game's March release fast approaching, it won't be long until we find out.

Just Cause 2 is due out for the Xbox 360, PS3 and PC on March 26.