The game is Operation Flashpoint: Cold War Crisis. It's the work of a pair of Czech brothers at Bohemia Interactive Studios, and it is published by Codemasters. It was finally released a few short weeks ago.

And it is very, very good.

In fact the biggest problem with the game is knowing where to start describing it. There's so much to tell. On one hand we could just say "This is fantastic, go and buy it NOW!" and leave it there ... on the other hand we could go on for hours.

Okay, hours it is. Let's get the comparisons out of the way to start with.

It's more realistic, complex, considered and tense than an online actioner such as ... ermm ... Counter-Strike for example. It's definitely a tactical sim but it has a much broader scope and tension than you get in claustrophobic titles such as Rogue Spear, or Swat 3.

Instead it builds on all the best bits of those titles - and a few more besides - takes them up a notch, and delivers a game that could be described as a first-person combat or battlefield sim.

Flashpoint is set in 1985. Gorbachev has just taken over control of the USSR and the old guard are unhappy at his moves away from hard-line communism. So a rogue general launches an invasion of a small Nato-protected island in a fictional remote island group where control is split between East and West. The general seems to want to precipitate World War III so he can restore the Soviet Union to its glory.

This story unfolds through the single player campaign, which is about 45 missions. Over the course of the war you will play 4 different characters: an infantry private who will work his way up to squad commander by the end of the war; a tank commander who will wind up leading a tank platoon; a chopper pilot who will graduate to Apaches and finally get a run in the fixed-wing Warthog; and also a special ops commando, going behind enemy lines in the dead of night.

It is partly this variety that takes Flashpoint beyond other tacsim titles. The ability to jump in and pilot/drive virtually any vehicle present in the war is not just a gimmick - it is all part of the battlefield simulation. You will be called on to move your squad in a five-ton truck, or command your tank platoon, or fly ground-attack missions in the Apache, and all of those tasks feel like and play like a core part of the game.

The integration of vehicles also adds to the game's incredible feeling of freedom and open-endedness.

For starters, every inch, every tree and every bush of the 100-square miles of each of three islands is modelled. You can pick your own path. You will have to refer to your map and compass to stop from getting lost. You can even navigate by the stars that are painted in the sky!

But it is also seemingly up to you how you complete a mission. Take for example a spec ops mission to take out some T80s that are parked up at a Russian base. You have satchel charges, and you only need to sneak around and take out two, and successfully make it back to the extraction point to complete the mission.

But what you could do, is sneak up to a T80, jump in, and do your best to wreak some havoc with the main armament. Of course, then two minutes later a couple of Mi-24 Hinds might fly in to the rescue and take you out, if the RPG soldiers don't get you first.

Or, you could sneak over to the parked Mi-17, fire it up, and loose off as many rockets and chain-gun rounds as you can before the Shilka crew gets to their AA weapon and takes you out. Alternatively you could kill the Shilka crew first, climb in and try to take down the Hinds and then ...

You get the idea.

This freedom of action extends throughout the game, and it really does make you feel like you are making the decisions, just as you would if it were real. It also makes you feel more responsible for the outcome of the missions. Sure you could do any of the heroic things suggested above - but they're suicidal. Do you want to put the mission at risk for your own glory? Go on then, but it's on your head.

In terms of gameplay, it's probably fair to say that Operation Flashpoint is aimed at gamers who were at least born by 1985, the year of the game's setting.

The emphasis is clearly on tactics, planning, and the kind of cautious approach you might expect if you really were going to be shot at. Before too long you will be called on to take command of a squad, and that means kitting out and issuing sensible orders to 7 or 8 other soldiers, on the fly and under fire.

You will not get far if you plan to charge around guns blazing, and don't look for the 'jump' key because there isn't one. In fact you'll spend most of your time on your belly crawling from bush to bush and freezing every time you hear the rumble of a tank - although, when the bullets start flying the sense of total confusion and adrenaline rush are better than any actioner.

It's realistic in the sense that one bullet will kill you more often than not, and if you survive three you're very lucky. It will probably be because you've been shot in the legs and won't be able to do anything other than drag yourself around by your fingernails. On the other hand, it's playable in the sense that if you can radio a medic who's still alive, and he gets to you before you're finished off, you can heal.

The game is also tough. Driving a heavy vehicle like an M113 down a steep slope makes it pretty hard to stop. In fact it's easier to roll than to stop. Flying a helicopter is pretty damn hard. Fixed wing planes are even harder, but that's mostly because the mouse is not reversed so you are likely to instinctively dive just when you meant to pull up. (For some unfortunate reason joysticks are not presently supported).

The AI is very impressive, with friendly and enemy forces reacting believably to battlefield events. They take cover, return fire, and run away at appropriate times. You will seldom spend time swearing at your stupid squad-mates for doing something like charging at a BMP with a plastic fork and getting your whole team killed as a result.