While the story as a whole doesn't offer much, it has amazing moments, like when you nervously approach the strange, organic wonder that is the long-buried alien structure. When you find yourself in zero-G it's a real pleasure, and the first appearance of your squid-like foe genuinely terrifying.

The frozen jungle is stunning. It's here that you come across your alien friends all kitted out in their winter best, dropped off by giant flying metal kraken-beasts like a mom leaving her kids at school: humming, ice-dagger firing exoskeletons that can leap in the air and, with a neat tilt, fire themselves in your direction in a flash of spinning blades.

Thing is though, fun as it certainly is at first, after a while of this you first realise that Crytek have suddenly got you playing a different game. And that game is Medal of Honour: Alien Assault. Everything you learnt and loved in the first half of the game becomes a sequence of ally-protection missions, sitting in the back of jeeps firing at the air-squids overhead, sitting in anti-aircraft guns and knocking even more of the threat from the sky, a truly awful level in which you pilot a craft that handles like a garbage truck with wings...the list goes on.

Now what we're about to say could be considered a spoiler - after the crappy flying level, where you end up is the last level. This place is honestly the setting for a whole bunch of too-ing, fro-ing and disappointing boss battles that deliver little more than the initial wow factor. And as for the actual moment it ends - forget crap Call of Duty endings, forget even Far Cry - the desultory 'here comes the sequel or, more likely, the expansion!' sequence Crysis ends on is an outright kick in the teeth.

Which makes it all the more lucky that the first thing we did having completed the game was start running through our quicksaves and getting back to the free-form goodness we were reveling in only four hours earlier. Crytek are simply not quite as good at creating scripted action as they are at action-bubble delights, and when they're so good at the latter, the fact sticks out like a sore, frozen alien thumb-appendage.