Initially, Singularty reminded me a lot of Bioshock. In fact, initially, it looks like a complete rip-off of Bioshock. The art style is the same, the inventory system is the same, and the skill set is pretty similar. However, after about the first hour or so, this feeling of playing a copy fades, and the game comes into its own.
Singularity is set on a fictional russian-controlled island named Katorga-12, on which exists a newly-found and powerful element known as Adam. Oops, I mean E-99. Of course, E-99 experiments result in chaos and mutations, and it's these mutants that you must deal with on your way through the story. Some mutants phase out of time and can't be hit, some are blind and react to sound, and others are just hulking behemoths. In addition to the mutants, the army are out to get you and stop you finding out too much about E-99.
Pretty early in, you will come across a TMD, or Time Manipulation Device, which, allows you to manipulate time itself, although interestingly, it manages to avoid the now-overused bullet time feature of most other games. What the device does allow you to do is freeze a section of enemies, age them into dust, or mutate them so that they can attack your enemies. I was initially sceptical about the TMD, because I was expecting the typical bullet-time method, but it actually works really well, and adds a nice bit of variety to what might otherwise be a fairly cookie-cutter FPS. As you progress, you can learn new abilities, earn new weapons and customise your TMD. Weapons are fairly standard shotguns, machineguns and rocket launchers, and although not particularly special on their own, the way they 'feel', and the way enemies react to them are frankly excellent. Shoot an enemy with a shotgun and he will fly backwards, shoot an arm and the enemy will lurch to that side, and the bullet wounds are some of the best I've seen.
The graphics are very pretty, and as I mentioned, the art style is very reminiscent of Bioshock, thereby making it also reminiscent of the Fallout series. Although it feels a little overdone now, it suits the game very well, and I can't really imagine the game working in a more serious tone.
Without wishing to spoil anything, the way the game ends is absolutely excellent, and something I really didn't see coming until it was literally upon me. Big thumbs up on that front.
In summary, if you liked Bioshock, you'll love Singularity. I actually enjoyed Singularity more, but it plays in a very similar way, so fans of Bioshock should find something to enjoy here. A great story and fun mechanics make this more than just another generic FPS.