Slowly, the door slides open. Your heart beats faster than a death metal drummer as you edge inside, globules of sweat streaking down your cheeks, sphincter clenched, every sense straining for the smallest sound, the minutest movement. Behind you are the rest of your squad - Corky, Dorky and Ken. Good lads every last one of them. You move further inside, slicing the pie, covering your angles, just like sarge taught you at drill camp all those years ago. Suddenly, a thunder crack breaks the silence and all you can see is the ceiling, and the smirking smug expression on the face of your killer who's been hidden behind the door all along. A one-shot kill, you had no chance. Game over. Reload. Start again.

Sound familiar? Well, if you're a fan of tactical shooters, then it probably will. Sure, we all love a bit of realism, lashings of tension and that warm glow of self-satisfaction that always follows the successful completion of a Rainbow Six level. But let's be honest, at some point or another, we have all felt that biting urge to hurl the controller aside, pick up our Xbox and toss it out of the nearest (and preferably highest) window when we've just been killed with a single shot... for the 36th time in succession.

Close Combat: First To Fight, a squad-based shooter set during a fictional future war in Beirut - in which the US naturally has intervened - is different. While it is a hardcore, fully tactical and realistic squad-based shooter, it's also more forgiving than its Rainbow Six counterparts, and subsequently, considerably more accessible and far less frustrating.

Strangely enough, much of the magic lies in its difficulty settings. Stick it on the easiest level (Recruit) and suddenly you're playing the game that Ghost Recon 2 should have been. It's a superb middle ground of frenetic firefights interspersed with lashing of tense, tactical calculated attacks and topped off with a damage model which lets you make mistakes, but never lets you be gung ho.

Yet ramp it up to Simulation mode, and it becomes a somewhat different game, one that stacks up to the slow-paced tactical sneakathons of the Rainbow Six series in almost every department, without ever being so utterly merciless as its rival loves to be when you make a mistake. So what you're actually getting is two games in one, with a couple of middle-ground difficulty levels thrown in for good measure. Not bad at all.

Of course, the true test for any tactical shooter is its ease of squad control and the intelligence of both your sidekicks and your foes. Thankfully, First To Fight excels in all of these departments.

Let's start off with the control interface, which isn't only straightforward but powerfully intuitive too. Directing your troops simply requires you to point where you want them to go and press A, while the context-sensitive command system automatically offers you other options - such as storming a room or picking up an enemy weapon - as and when they become available.

It's not long before you're directing your squad of highly trained US Marines - who move and cover themselves just like their real-life counterparts - without even having to think about it, hugging walls and flanking the enemy while your men lay down suppressing fire. Perhaps the game's most notable merit is the intelligence displayed by your troopers, who actually follow your orders to the letter, and display a superbly balanced, almost lifelike array of reactions and abilities when under fire. Unlike many other games of this ilk, you'll rarely if ever find yourself screaming obscenities at your television as your men bunch up and crash into one another. Neither will you ever feel as though you can simply send in your three team-mates to do all of the work for you.

And that's just for starters, because Close Combat also gives you the opportunity to call other forces into action, including helicopter gunships, mortars and snipers, all of which must be combined with your ground-based foursome in order to overcome often overwhelming odds. You and your men can also man any enemy weapon, ranging from truck-mounted machine-guns to hulking cannons, adding yet another tactical option to your already bulging bag of strategic tricks.

The enemy AI is almost as impressive, though it does occasionally fail to see you, even when you're standing right in front of it. But more often than not, your adversaries display an acute awareness of their surroundings and utilise them with lifelike intelligence. Enemies duck and weave, seek out cover and fall back when under heavy fire. Aim at their heads and they'll stoop down or jump behind a wall, popping out for a split second to let off a volley or assess their situation, before disappearing behind their makeshift defences. More often than not you'll find yourself looking for an exposed foot or elbow, zooming in with your scope - which gently bobs, just like it would in real life - to execute a precision shot. Hit an adversary in the leg and they'll limp, shoot them enough and they'll pathetically hobble towards safety, virtually prone targets simply begging to be finished off.

First To Fight is also no slouch in the graphics department, perfectly depicting eerie, dilapidated cityscapes that have been bombed to powdery concrete stumps and claustrophobic enclosed confines, replete with subtle lighting and twisting tunnels. The action moves seamlessly from underground locales back to ground level, and missions are rarely restricted to just one monotone location.

There's also a well-paced soundtrack, which moulds itself perfectly to the action, and some ear-bleedingly realistic explosions and weapon sound effects that suck you right through the screen and into this fictitious yet brutal war-torn world. It's just a shame that the same attention to detail wasn't lavished on your squad's verbal responses, which become teeth-gratingly annoying well before the close of the first level, let alone the game.

Close Combat is a triumph, an action/strategy shooter that will appeal to all lovers of squad-based warfare, whether you like it slow and strategic or more in your face and furious. Sure, there are a few problems too, most notably some cringe-worthy graphical oversights - weapons spinning in mid air for example - and the fact that you can't climb over low walls or fire through higher, thinner ones when enemies are using them for cover, but ultimately, this is a game of huge quality and entertainment, and one which shouldn't be overlooked just because it requires you to think more than the likes of Unreal Championship 2 and Doom 3. Try it, you just might like it. That's an order soldier. Diiiiiiis-missed!

1. A wide range of well-balanced difficulty levels makes the game bother accessible and challenging to all-comers.
2. Superb usage of real-life tactics and some genuinely intelligent AI make for a realistic and intense experience.
3. Graphically and aurally impressive throughout, though squad dialogue is overly repetitive.
4. Intuitive controls and an easy-to-use command system make it easy to execute and master the game's many strategic subtleties.

1. Annoying graphical glitches and the odd dodgy AI line of sight moment belie the game's otherwise top quality presentation and immersion.

One of the finest and most accessible tactical shooters on Xbox, slightly marred by clumsy oversights and bugs.