Good storyline, addictive gameplay and a few edge of the seat moments. What more could you want?
Graphics are good but do have some rough edges. Sound is atmospheric and immersive and the controls are easy to master, even with the inclusion of the TMD ( Time Manipulation Device ) to complicate things beyond the good old aim and fire assault rifle. The game centres around the Russians discovering a new element on a small island off the mainland coast and the research facilities set up there to exploit it's many possibilities; including but not limited to weapons adaptation and human mutations. All the usual suspects are present from the mad scientist to the token good looking female ( although this isn't a Bioware game so don't expect any romance ) and all fit in nicely to the niches intended for them.
The gameplay itself is well balanced, not too hard or too easy and the frustrating moments found in many games of this type are kept to a minimum; even the boss fights are well thought out once you work out how to beat them and are rewarded with nice cinematic sequences. Another plus for this game is that those same cinematic moments don't get in the way of the gameplay which is a mistake made by other developers ( metro 2033 for instance ).
One minus for singularity is the convenient placement of old recordings to move the story forward and give the player the information needed to get past the next obstacle. These spoil the immersion somewhat as they are all exactly where they need to be when it would have been better handled by documents found and recorded by the player in a diary of sorts for example; so instead of having to work out which piece of info was relevent it's right there like a neon sign flashing 'warning' right above the door to where the danger lurks. As an example of this you find a recording saying that a particular creature is blind and can be sneaked past just before you encounter them. This does not apply to the many messages scrawled on the walls which in many cases are even more helpful but there is a definate reason within the story for them being there.
All in all this is an enjoyable and immesive game that I liked very much, even with it's few rough edges, a solid 8.5