Eidos has high hopes for Just Cause, and on the face of it there's no reason it won't be a huge success. The game seems to have it all: a huge free-roaming world; stunning visuals; land, sea and air vehicles; and explosive combat. It's a hard package to resist, and at times it really is irresistibly good, but it's far from consistent. Sight seeing action junkies looking for another free-roaming game will find a lot to enjoy, but a few kinks prevent Just Cause from rising into elite territory.

You play as Rico, a smooth talking, sleek, suave, agent, with a complete lack of fear. Extreme sports are like child's play to this guy, and that makes him the perfect man to take on Salvador Mendoza, the corrupt dictator of the fictional island San Esperito. Missions are handed out in typical GTA-esque fashion, with NPCs scattered about the huge island, ready to give Rico new main and side missions. It's simple enough to progress, with missions being split by type and clearly visible on the game map. Rico's goal is to bring down Mendoza, with the help of the island's Revolutionary Army and the Riojas drug cartel.

Main story missions are by far the most interesting and diverse, and see you take on numerous, often explosive objectives, but the side missions from the island's Revolutionary Army and the Riojas drug cartel are plentiful. You'll be thankful that so many were included, as the main story can be blasted through pretty quickly if that's all you focus on. By carrying out the side missions you'll get access to more safe houses (where you can save, and replenish ammo and health), new weapons and vehicles. In theory it's best to tackle these side missions as you progress through the main campaign, but other than a few hairy missions, you'll do just fine with what you're given.

Unlike the recently released Saints Row (which shares little in common with Just Cause other than its free-roaming nature) combat is handled by a handy auto-targeting system, where enemies within range are locked onto without you having to do much more than look in their general direction. Targets can be switched by using the left bumper, while the left and right triggers throw grenades and fire your weapon respectively. It's all relatively simple - that is until you unleash Rico's Hollywood stuntman moves.

Skydiving and parachuting are his main vices, and there are plenty of ways to get into the air. The most obvious is to jump off a cliff edge; doing so will start a free fall, and you can then open your parachute for a more sedate fall to earth. If you can't be bothered to trek up a mountain you can use your grapple gun to latch onto NPC vehicles, instantly sending you into the air with your parachute out. From here you can let the rope out for what seems an infinite distance, and go along for the ride, switching from vehicle to vehicle if you want.

It really is a stunning game

Just Cause isn't a GTA clone in the traditional sense, but you can most definitely hijack vehicles. Cars, bikes and trucks are the most common, but you can just as easily drive boats, or take to the skies in a helicopter or aeroplane. This range of vehicles plays right into the hands of Rico's daredevil ways, and he's more than willing to throw himself onto the roof of a moving car or plane, before jumping to another vehicle. It's insane, and can make for some truly memorable moments.

Army forces make mincemeat of vehicles, so hopping from one to another plays a big part in staying alive. Imagine leaping over the blades of a helicopter, before spotting a fighter jet screaming towards you, missiles locked and loaded. In the average game you'd already be dead, but not here. Within a split second you can leap from the chopper and onto the plane, open the cockpit, push out the pilot and take over the controls. Moments like this make playing Just Cause an experience to remember, but not one that's without faults.

Combat is explosive, but feels weak.

For a game with such a focus on combat this aspect feels rather weak. Enemies go down without the need for much skill, and you can often survive enemy onslaughts by simply continuously running, with the AI not being able to hit you unless they get in close. Driving AI is far more effective at halting you, but not in a way that seems realistic. The island's police force is almost suicidal in its attempts to drive you off the road, making running on foot across the island a much safer, albeit slower option. Death isn't much of a problem, as most missions feature checkpoints, but being blown out of the air without warning can get a little annoying.

The island itself is stunningly beautiful, and the sense of scale is breathtaking. Pop-up and occasional frame rate stutters slightly ruin the view, but it's hard not to take in the scenery with anything other than a grin on your face. The denseness of the forest combined with some wonderful lighting gives the island a real vibrancy, and at times you'll sit there, watching the night turn to day - ideally from the seat of helicopter or while parachuting from high altitude.

All this beauty comes at a cost though. The island is so huge that you never get to learn its layout, and while all the trees and sea look fabulous, it all looks the same. Urban areas are in the minority, and these are pretty similar to one another, meaning the island doesn't feel as real as the play areas in Saints Row or the GTA games. Your PDA features a map, but it lacks the GPS function as seen in Saints Row and Test Drive Unlimited, so you'll find you have to constantly pause and check your position, unless you've decided to hijack an aircraft or walk as the crow flies towards your destination.

Despite its problems, Just Cause can be exhilarating. A combination of motion blur and awesome explosion effects gives an overall level of visual quality that can at times rival CGI - it really has to be seen to be believed. Audio is equally dramatic, with booming sound effects being used when needed, and a pumping soundtrack kicks in whenever the heat turns up a notch. Voice acting isn't too shabby either, although it's by no means the game's high point.

There's no multiplayer to lengthen the game's lifespan, but 50 achievements have been included for Xbox 360 players to earn. These are pretty well thought out and encourage players to get the most out of the game, but a few bugs prevented a couple from being awarded during my time with the game. Bugs can also be seen elsewhere, with cutscenes not loading properly, missions breaking due to objectives not being marked as completed, and numerous clipping problems that see Rico walking through objects. These little bugs really shouldn't have made it into the final release of the game, and do hurt the overall experience.

Just Cause's biggest draw is its huge island setting, but it's also what prevents the game world from feeling truly alive. As much as soaring through the sky in a fighter jet, before freefalling hundreds of feet, and then parachuting to your target destination is great fun, that's pretty much what you do, over and over again. The island lacks character and this is echoed throughout the missions themselves, making a game that is undeniably gorgeous, but lacking spark. Sight seers will certainly get their money's worth, and the main campaign is often enjoyable, but Just Cause is a long way from being the classic it could have been.