If you've owned any home console or have been playing PC games in the past four years or so, the chances are very high that you'll have at least heard of Splinter Cell, even if you've not been fortunate enough to have experienced it firsthand. Endorsed by the king of behind-the-scenes anti-terrorism fiction, Tom Clancy, the Splinter Cell franchise is most renowned for its cerebral stealth gameplay and cutting edge visuals, and more recently its unique multiplayer modes. Tom Clancy's Splinter Cell: Double Agent marks the fourth entry in the series on home consoles and while it's certainly not a major leap forward in most respects, it's still one of the finest stealth action games you're likely to stumble across - at least until the next iteration in the series.

With each new instalment in the Splinter Cell series, Ubi Soft attempt to push the envelope in certain areas. Pandora Tomorrow introduced the hordes of Splinter Cell fans to the sublime two-on-two spies vs mercenaries multiplayer matches, while Chaos Theory added a wealth of new close-quarters combat manoeuvres, along with an impressive co-op mode to boot. Despite my previous statement on how Double Agent doesn't especially reinvent the franchise - in terms of gameplay at least - let it be known that Ubi Soft certainly put a lot of effort in as far as making the story a lot more interesting is concerned; I was never particularly enticed by the hackneyed, clichéd and wholly uninteresting stories found in the first three games, but Ubi Soft has attempted something inventive with Double Agent and completely nailed it. As usual you take control of Sam Fisher, a covert agent working for Third Echelon, a black-ops division of the National Security Agency. Flown into Iceland to investigate some suspicious activities at a geothermal plant, Sam successfully puts a spanner in the works. However, upon extraction his superior, Irving Lambert, is aboard the chopper to personally break the news that Sam's daughter was killed by a drunk driver. Sam slips into a deep bout of depression and is unable to concentrate on his NSA duties.

Months later, Lambert offers Sam the rank of an unofficial deep cover agent and he accepts. The NSA then proceed to turn him into a notorious criminal, resulting in Sam's imprisonment in the same cell as a core member of the John Brown's Army, a domestic terrorist organisation. Sam's mission is to escape with the JBA member, join and secretly infiltrate the organisation to provide the NSA with information on them. However, this is where Sam's - or rather, the player's - dilemma begins, as both the NSA and the JBA have vastly different views and opinions on what is ethical and what isn't - and since both organisations oversee each and every one of Sam's missions, you invariably find yourself with conflicting mission objectives. This is implemented further with the new trust meters - you have a trust meter for each organisation and each goes up or down depending on which objectives (usually optional secondary objectives) you successfully accomplish and which you choose to ignore. For example, while Sam and the imprisoned JBA member, Jamie Washington, are escaping from prison, the NSA is very insistent that you only incapacitate guards and refrain from killing them - however, the JBA take great delight and trust you a great deal more if you snap some prison guard's necks while breaking free. Furthermore, the choices you make throughout the entire game all eventually come together to determine the final outcome of the story; there are three completely different endings to be seen. What bearing this will have on the story of the next inevitable Splinter Cell game remains to be seen, but for now it should certainly prove satisfying for players to know that they're actively influencing the flow and direction of the story, rather than simply following it from an outsider's perspective.

Double Agent has three difficulty settings - the severity your choices bear on the respective trust meters being the biggest change in how much of a challenge the game presents. Overall, Double Agent's difficulty remains similar to past outings. As always this is still a stealth action game, not a run-and-gun, balls-out shoot 'em up and Splinter Cell is striving for realism, so you're not going to be able to run around shooting up tons of guys while taking a barrage of bullets to the chest. Sam's repertoire of moves hasn't really changed; you can still duck, slink along walls and behind other cover, use zip-lines, shimmy up and down poles and perform all the other acrobatic feats he's been wowing us with for the last four years. And it's a good thing too, because Double Agent's AI is quite a step up from what was seen in Chaos Theory, plus there are a lot more enemies patrolling areas in many parts of the game.

The use of pure stealth is even more abundant now, especially in the missions that take place inside the JBA's base of operations. Each of these missions give you roughly thirty minutes to successfully complete a wide range of both NSA and JBA objectives and, seeing as you're deep inside JBA territory, you're not allowed to use any attacks or gadgets to complete these missions. So while you might usually knock a few guards out before hacking a computer terminal and making a getaway, or use the pistol or a smoke grenade to get yourself out of a jam when confronted by an enemy, the JBA base missions require you to do your hacking, snooping and sleuthing right under your enemies' noses. As is the case in every mission, either of your trust meters hitting zero results in mission failure, so being devoid of any kind of tactics other than not being seen doing anything suspicious make these missions a lot tougher than the field assignments. However, this does bring me to one of the few flaws; the gameplay - none more so than when sneaking around the JBA's HQ - is vastly trial and error oriented. All too often you'll make a mistake that compromises your success and you then have to reload a past save and start over. Luckily Double Agent auto-saves at fairly regular intervals and allows for a manual save at any point, so the trial and error turmoil is nowhere near as severe as it could have been, but after so many years of stealth based games isn't it time that a developer came up with a way to remedy the tedious action of constantly reloading a game simply because the player made one mistake?

And make mistakes you will, as - in a move that I cannot even begin to fathom - Double Agent manages to take a huge step back in terms of letting the player know exactly how well they're keeping themselves undetected. Anyone who's played Chaos Theory will remember that that game utilised an impressive combination of on-screen meters that informed the player of not only how well hidden they were - obviously lurking in the shadows while progressing kept you more hidden than frolicking around where any enemies with a half decent pair of eyes could spot you - but also of how much sound they were making, so even if you kept to the shadows you still needed to keep your wits about you. Double Agent does away with the sound mechanic almost completely, instead opting to keep the player informed of their level of ninja-like invisibility with a light both on the game's HUD and mounted on Sam's back. If the light is green then you're well hidden enough to be going about your shifty spy shenanigans freely; if the light is yellow then it means that patrolling guards aren't completely aware of your presence or activities but are suspicious enough to start searching for a possible intruder and if the light is red then you'd better find a place to hide, because you've been detected and will likely end up dead if you don't vacate the vicinity. The three-level light warning system works, but why Ubi Soft would choose to use that when they had an almost perfect system in the previous game is beyond me.

While carefully negotiating each environment is a big factor in your success, your various means of initiating hostility also play a significant part in most missions. The mechanics haven't changed at all; the controls, implementation and feel are all exactly the same. When using a gun Sam moves a hell of a lot slower, so there'll be no running around while firing off bursts of gunfire - not that actually shooting someone is really a lot of fun here. As was the case in Sam's last three outings, there's no visceral thrill in having a bullet connect with an enemy's head (or anywhere else for that matter). The big fun comes from using Sam's hand-to-hand abilities, combined with his infamous array of gadgets. Whistling, hiding behind a wall and waiting for a suspicious guard to arrive before jumping out and punching him in the face is still highly entertaining and satisfying. Plus the assortment of gadgetry on offer is phenomenal; night and thermal goggles make a return, as does the EMP pistol (handy for temporarily cutting off light sources) and the amount of attachments for your rifle, such as a few grenade variants and a camera that can stick to walls, allowing you to suss out the best way to enter a room for example, are compelling and offer a wealth of ways in which to approach almost any given situation. Completing special marked secondary objectives throughout the game also unlock additional gadgets for you to play around with.

In addition to its lengthy enough single player campaign, Double Agent also once again marks the return of the series' popular multiplayer matches. The concept remains identical - you have two small teams (although the number of players per team has been increased from two to three this time around) of spies and mercenaries - the spies are trying to hack and download information from terminals littered around each map and it's the mercs' job to stop them. The spies play similarly to Sam, although they're a lot faster and more nimble, so they're can make full and extensive use of each and every nook and cranny in the ten or so multiplayer maps. Furthermore they're equipped with a wrist mounted device that can be used to disable the weapons systems of the mercs, break glass, knock out light sources and also to download those crucial computer files. The mercs play a lot differently; their view is first person and they're nowhere near as agile as the spies; however, the game balances this out by having the mercs pack a bloody great big gun with an unlimited amount of ammo clips, along with a few other gadgets and vision modes.

In an interesting twist, Double Agent prevents players from playing on every multiplayer map straight away - you need to have gained experience before the additional maps are unlocked. This is highly beneficial though, as knowing the ins and outs of a map is absolutely crucial to winning a match. It's no good just rushing out and trying to hack a terminal or hunt down spies - if the other team has an intricate knowledge of their surroundings then they'll quickly get the drop on you and wipe you out before you have time to blink. On top of the competitive matches, Double Agent also includes a series of co-op missions, which will have up to three players controlling spies and pitting you against AI controlled mercs. Unfortunately they're disappointing when compared to Chaos Theory's story-driven online missions, which had two players lifting each other over walls and generally sneaking around and attempting to complete objectives in co-operative missions.

Splinter Cell has always excelled in its presentation and Double Agent is no exception to that rule. While the textures along with the lighting, shadow and other environmental effects are all vastly improved over the last game and worthy of being referred to as next-gen, this iteration's character models really stick out as an immense leap forward. The lip sync is practically spot on throughout the entire game, animations often look frighteningly natural and each and every intricate detail really stands out and looks absolutely fantastic. The sound is of varying quality; as usual the music is pretty "meh" (as the Internet kids say) and any guns you'll find yourself using lack any meatiness or satisfying kick to them, but the ambient sound and voice acting is top notch. One gripe I have is that the framerate can get quite sporadic; it's usually around the thirty frames per second mark, but can dip noticeably in spots.

Tom Clancy's Splinter Cell: Double Agent is certainly not going to win over anyone who's opposed to the series or stealth games in general, as the gameplay remains wholly unchanged and any problems specific to the genre return in spades. However, almost everything it does, it does extremely well. The single player campaign is lengthy and - for the first time - includes a genuinely interesting and involving storyline, the competitive multiplayer modes add a lot of lasting value to the package and the quality of the presentation is certainly on par with what we've all come to expect from a Splinter Cell game. It may be a sidestep or even a disappointing step back in some areas as far as the series is concerned, but it's still an awesome game that any fan of Sam Fisher or stealth games is going to enjoy immensely the entire time they're playing it.

Reviewed by Mark Reece for AceGamez (All Rights Reserved).