BioShock 2 was first released in 2010 by 2K Games.
Personally, I think BioShock 2 just edges it over its predecessor, because the setting is really interesting (rather than hunting Big Daddies, in this one you get to play AS a Big Daddy), and also because this sequel has a decent multiplayer side (the first BioShock had no multiplayer). And also because the game mechanics are slightly more detailed than the first game.
I also think the ending is better in BioShock 2. Of the three possible endings, the one I got I thought was absolutely brilliant. Brought a tear to the eye…
BioShock 2 carries on a fine tradition of emotional, dark action adventures on the PC (and other systems), and is still well worth a play any day of the week.