That pesky butterfly effect keeps rippling outwards for the poor Prince. Having unleashed the Sands Of Time, laying his kingdom to waste, and then journeying to the Island of Time to put things right, the Prince expects that finally, he can return back home to the Babylon he knew before the Sands reached out and corrupted the world. Only we know that's just not going to happen, don't we?

At the end of Warrior Within, when the Prince returned his kingdom to the way it was before he unwittingly unleashed the Sands, he thought he had altered everything. Well, he had, except for the small question of his fate. He returned the world to how it once was, wich meant that all the dark powers in the world who had sought to wield the Sands of Time were now very much alive, and still hungering for them.

The wheel had come full circle, and as the final part of the Prince Of Persia trilogy sets off, we find ourselves not so much back to the beginning, but at an alternate beginning, where the Vizier still walks the Earth, and where, in the Prince's absence, he's been able to make the Sands of Time his own. Now, in this final struggle, the Prince must put an end to-the Vizier once and for all, and bring peace back to his native Babylon. But it's not going to be easy, especially because he's been infected with the Sands himself, but more on that in a bit...

By returning to the beginning of the Prince's story, and having him retain all the strength and power he developed during the second game, the third and final chapter is a perfect blend of the best of both games. The combat is there from Warrior Within and runs like a dark vein throughout, while the Sands Of Time are back too, offering more time-meddling puzzling and head-scratching. This is the best of both worlds, and then some. New to The Two Thrones are the Prince's vastly improved killer moves. If the keywords for the previous games were 'puzzles' and 'combat' respectively, this time it's most definitely 'stealth'.

Because Babylon is occupied by a mysterious army, the Prince is effectively hunted at every turn and must use caution just as much as a sharp blade. Before getting into a ferocious swordfight with half a dozen or more enemies, there is always an option for stealth that presents itself. By looking around the environment there are always an option for stealth that presents itself. By looking around the environment there are always ropes or ledges you can hang from in order to spring a surprise attack. By doing 5o, and by keeping quiet, you can, if you time it correctly, wipe out entire legions of enemy warriors without alerting their comrades in arms to your presence.

A stealth kill can only be carried out successfully if you strike when your dagger flashes blue. Time it right and you make the kill, but get it wrong and you'll have to fight your way out with nothing but a few tanks of time-reversing sand and acrobatics to save your skin. Neither option, be it stealth or full-frontal attack, is easy, but the choice to do either adds real depth to much of the game. Naturally, the harder the enemy the more times you have to perfectly time your strikes with the flashing of the blade, but pull off a stealth kill on a 30-stone, scimitar-wielding, fire-breathing cow-man and it's deeply satisfying. However, despite the new combat options, nothing quite makes The Two Thrones rock quite as much as The Dark Prince, a flame-haired lunatic with a penchant for choking people with his barbed-wire whip.

The Dark Prince is the badass alter-ego of the regular Prince, a character born of the Sands Of Time, and one who is slowly eating up the Prince's personality by randomly turning up throughout the game and inhabiting his body. His arm, infused with a spiked chain known as the daggertail, is a stunning weapon, part whip, part portable guillotine. He can swing from distances too far for the Prince to reach, and lower the daggertail silently down over an enemy's head like a noose before yanking it upwards with a wet wrenching noise. You can imagine the mess that makes.

The new Prince's abilities and the daggertail, have enabled the developers to construct bigger, more tricky environments that push this final instalment to the very limit. Gone is the claustrophobic feel of Warrior Within, replaced by a grander, more deadly Sands Of Time-style environment, one that unfurls every step of the way with increasingly spectacular gameplay.

All the moves from the earlier games remain, but in addition to these you can now jump diagonally, or swing vast, incredible distances with the daggertail. By learning how to use this weapon effectively, you can perform graceful, but staggeringly deadly moves with it. If you see an enemy on a balcony far below, rather than slowly making your way down via a series of ledges and poles, you can perform a single manoeuvre and have his head on the floor before his body knows it's missing. First you run along a wall, then tear down a long tapestry with the daggertail. Then, as you rip through the fabric you dive across a chasm, swing on a pole, then bounce off a wall and latch the daggertail round his neck, ripping his head clean off. If, as is often the case at the beginning, you screw up, you can either reverse time and try again or just whip him into submission. If he calls for help (which every enemy now does, so beware) the daggertail can keep throngs of them at bay at once, lashing anyone who comes near with infected razor edges. Between Farah, Kaileena and the Dark Prince, as a secondary character old flame-head wins hands down every time.

But, for all the Dark Prince's strengths, he is still very much a creature of sand, which means if he doesn't keep feeding on the stuff, he'll eventually just collapse and die. Being a slave to time adds a further new element to The Two Thrones, for while the Dark Prince has no trouble slicing through enemies, the clock is his deadliest foe. He has to constantly move fast to stay alive, whereas the true Prince can take things more deliberately and thoughtfully. By combining these two very distinct styles of gameplay, there is never a moment, not a single second in the game where you're left wanting for something to keep you entertained. And as if to make doubly sure, there is a rich, dastardly plot woven throughout to keep you guessing.

Nothing is what it seems, and as the Prince slowly realises this, it gradually becomes clear just how well planned the whole trilogy actually is. Throughout the game, as the Prince moves from the slums below the city, through to the upper realms of the hanging gardens and royal courts, you'll occasionally be thrown into situations that require more than an ability to swing around like a turban-wearing monkey. New chariot race modes have been introduced, and while these are used sparingly, they make a great break from all the fighting with your enemies and flirting with Farah. They're fairly simple and involve little more than steering wild horses through the narrow streets of Babylon, but the races are a great mechanic for moving the action between locations in the game, and they illustrate how big this final episode actually is. There's no retreading old ground like in Warrior Within or exploring for secret rooms and treasures - this is an out-and-out hunt, a final push by the Prince to mend all the past wrongs.

As Babylon expands you're often torn between objectives. The Dark Prince yabbers on inside your head about seeking revenge (he can be quite funny when he's not eviscerating people), while the good Prince sees his subjects in danger and wants to rescue them. This often involves a complex set of puzzle-solving, and all credit must be given to the team for once again producing the kind of devious conundrums that sets the Prince of Persia series apart from its closest rivals. One puzzle, set in a giant masonry workshop, sees the Prince trying to manoeuvre a colossal statue through the interior of the workshop and out the other end. It's like pushing a 50-ton climbing frame through a maze, and is incredible stuff. You will pull your hair out at the roots, we almost guarantee it. But, sadly, other things also have the same effect...

A lot of the niggles of the first two games have been addressed in The Two Thrones. The tone is right, the feel is superb, the camera is faultless and the gameplay has been taken up another notch, yet we still have a few quibbles. Some checkpoints are infuriating. At some points you are expected to navigate through a labyrinth of traps only to face a pack of bastard-hard demon dogs at the other end. The battle may take three, four, or even five goes before you've learned how to defeat the fiery mutts, but every time you're sent back to the beginning of the puzzle section that precedes it, and forced to do it all again. We found ourselves literally screaming in frustration. A game should only make you repeat that which you can't beat, not ten minutes of tasks you could do blindfolded that you've already done a hundred times over.

Another thing is the random distances the Princes can both jump. For the sake of getting a Prince from A to B, sometimes liberties are taken in the distances they can or cannot jump. What may have been a deadly distance earlier in the game becomes jumpable. We spent an age, with no time-reversing Sand, wondering how to get to the only visible ledge. Turns out that, because it's the only way to go, the Prince can somehow manage it.

Technically, this is the best of the three games in the series. Besides the new game mechanics, superb story and a great secondary character in the Dark Prince, everything under the bonnet purrs beautifully. The eye can sometimes see right to the horizon, observing the burning buildings in Babylon, while other less obvious but nonetheless impressive touches, such as red embers rising in the breeze, give The Two Thrones a classy feel. The voice-acting is fantastic (the Prince is still American though) and the environment design, while lacking the whirring buzz-saws and spring-loaded traps of the previous games, is just as fiendish to navigate. As we say, because of the new character abilities, levels can become open-expanses of traps.

For a series that has consistently proven itself at least three steps ahead of the competition, it was a daring move to give stealth a pop, but The Two Thrones handles it so well, and lends it such a fresh perspective it'll feel like you've never played a stealth game before. In fact, everything in The Two Thrones is crafted with such brilliance that you'll almost mourn the fact that it's the last of the trilogy.

It's a cracking, clever, and crafty title, packed with surprises and brimming with invention, and a game that makes sure that, once you've completed it, you'll want to go right back to the Sands Of Time and play it all over again, if only to spot all those clues that were there all along right from the start. We've said enough - go buy it already!

1. Picking out the best of the previous games, The Two Thrones strikes a perfect balance between combat and puzzle solving.
2. The plot! How devious, how tricksy, how did we not see it coming? We've said too much, but trust us, the pay-off is brilliant.
3. The Dark Prince. How cool? Okay, his hair makes him look like a satanic Gary Rhodes, but he rules whenever he's around.
4. It's huge. The new 'outdoors' feel, and seeing Babylon in all its glory, give a real weight and seriousness to the game. Sweet.

1. Checkpoint positioning can be annoying. We don't want to go back and re-do a stupid block-pushing puzzle, we just want to fight.

The best possible send-off for the series, and easily the best Prince Of Persia game to date. A classy little number.