One of the biggest challenges in life is pleasing everyone. Certain things are bound to rub people up the wrong way, but sometimes you can't help it. You can't please everyone all of the time, and this will cause problems. You'll please your mother by recording the gardening program she wanted to watch, but doing so will mean your younger brother can't watch The Simpsons. The following day you'll try to make up for this by letting him watch the horror movie you've rented, angering both your parents in the process, and nullifying the good deed you did the day before. Still, If pleasing everyone in your life is hard, imagine what it's like for Sam Fisher.

In Sam Fisher's latest Splinter Cell adventure Ubisoft wanted your actions to mean something, above and beyond simply completing objectives and successfully carrying out missions. In Double Agent your trust is on the line every step of the way, and every action will be judged by the people around you and by those watching you. With a pretty feature-complete build of the game almost begging to be played, I went undercover to see just how Double Agent will shake up the Splinter Cell series.

Reasons for Fisher's willingness to risk his life can be saved for our review later this month, but he's not in a good way, so takes on a job that will put him at the heart of a terrorist organisation, the JBA. Throughout the game you'll be working for both the JBA and the NSA (the good guys), with each side having its own set of objectives, often conflicting with one another. It's up to you to choose your path, but it's essential that you don't blow your cover or stray too far over to the JBA side - if you do the NSA will pull the plug, and it'll be mission over.

This new way of thinking is initially pretty baffling, and it wasn't until the first mission inside the JBA HQ that things really became clear, and the intelligent game design became apparent. By this time you'll have successfully helped a terrorist escape from prison, but back at HQ his colleagues aren't as willing to take you at face value. You'll need to carry out a test, to prove you're worth the effort, but the NSA has its own plans for you, making what seemed like a fairly simple obstacle course anything but.

Your mission objectives can be viewed on your more than handy PDA watch, and from here you can see what each objective will do to your overall trust from each party, with the consequences for completing or failing each. Although you're free to do what you want, if a certain action will reduce one of your trust meters to zero, you have no choice but to do the opposite. Your actions earlier on in a mission can often mean your preferred course later on will jeopardise the mission as a whole, so it's essential you keep track of how people view you.

Anyway, back to that obstacle course. The course itself is pretty simple, requiring Sam to navigate a number of sensors and make it through to a safe, but you've been given a time limit and that safe needs cracking. Once the time limit is up the leader of the group will return to check your work, and failure to do what's required will seriously hurt your cover. The problem is that the NSA's objectives also need to be carried out within the same time limit, so seeing as you've been left alone you need to do a bit of sneaking around.

Once the safe is cracked (a procedure that is either remarkably fiddly or requires a skill I'm not aware of) you can do a number of things. The NSA wants a trojan installed on the terrorists' computer system and a bug planted on an antenna that's located on the roof. Completing both of these tasks will improve your trust rating with the agency, but you don't want to risk everything in order to do so. In the end, particularly if you're new to the series or aren't familiar with the level, it's easier to play it safe and do the bare minimum, but with plenty of achievement points to unlock, completists will have to work incredibly hard to complete each objective and still remain trusted by both parties.

Presentation is top notch

Without playing through the entire game it's hard to tell how much of an impact your actions in each mission will have, but it has a strong influence on each individual level, especially if you're careless early on and fail a number of objectives before you've really got started. The core gameplay is still essentially what fans will remember - Sam still moves like you'll remember, hides well in the dark, and can use gadgets - but the double agent theme makes for a game that requires more thought, on top of nous required to carry out each basic objective.

While still being polished and tweaked, the work in progress build was still mightily impressive. The levels are large, featuring some of the best lighting and texture work I've seen on the Xbox 360, and the character models look superb. The frame rate is a little unstable, and became choppy in a number of areas, but hopefully this will be sorted before the game hits stores. Voice work, sound effects and music all seem up to the usual high standard for the series, and all help create what should be one the standout Xbox 360 titles for this winter.

The Splinter Cell series has been criticised for staying too close to its roots, but the same can't be said for Double Agent. The trust system makes Sam's latest outing seem fresh, and the redesigned multiplayer mode should be another great addition. Ubisoft rarely disappoints with its big franchises, and barring a disaster, Splinter Cell: Double Agent should be another huge hit. Look for a review close to its October 20 release date.