When it comes down to whether or not a game leaves a lasting impression on me, mood is a critical factor and rest assured, this stellar first-person shooter has plenty of it. Set in Rapture, an underwater city that was once an anarchical utopia ("No Gods or Kings. Only Man."), BioShock entices the player with intrigue, motivates them with horror and suspense, and rewards them with the continuous discovery of this eerily beautiful and ruined world. Once the game sinks its hooks into you, simultaneously filling you with unease and delight, you can't help but want to cozy up into it and hope that it never ends. As long as you don't mind a duely M-rated game, I would recommend BioShock to just about anyone.
In BioShock, you play as Jack, who at first seems like a simple enough protagonist, but by the end of the game, we learn that there is much more to him than the earlier parts of the game let on. After his plane crashes somewhere in the Atlantic, Jack finds himself caught up in Rapture, struggling just to survive, let alone escape. Guided through the vast city by a number of mysterious characters--all of whom have their own motives--via radio broadcast, the player faces constant adversity from what's left of Rapture's citizens.
There's the Splicers, whose minds and bodies have been wrecked by excessive modifications to their genetic makeup, leaving them violent and insane. They're also probably my favorite "common" antagonists of any video game, ever. Not only does fighting against the many varieties of Splicers throughout the game pose a fun challenge for the player, but they're also legitimate video game characters with an unmistakable depth to them; not just a random gameplay component like so many other games' bad guys. Then, of course, there are the iconic Big Daddies and the seaslug-possessed Little Sisters that they guard with their lives. These creepy little girls wander the city, extracting ADAM from corpses. If the player succeeds at killing a Big Daddy, he or she must then decide whether to save the Little Sister or "harvest" her for more ADAM. ADAM, in addition to plasmids (commercially-sold DNA-altering potions), essentially gives a person super powers. Therefore, more ADAM means Jack can become more powerful. However, harvesting a Little Sister also makes you a bad person and changes the outcome of the game. These are the sort of choices that the player must make.
As if that wasn't enough excitement, the player is constantly being threatened and pursued by Rapture's founder, Andrew Ryan, who would like nothing more than to have you "eliminated". He also bears strikingly similar philosophical views to those of Ayn Rand, and I think it's safe to say that BioShock is a response of sorts to Rand's fictional works. This is just yet another thing that makes the game so compelling and unique.
While adventuring through the city, the player may pick up a number of audio diaries. These recordings tell the stories of Rapture and its citizens, helping the player understand the city's fascinating history. Even still, greater secrets await Jack as the player nears the game's end and discovers the true meaning behind his arrival in Rapture.
All images are (presumably) the property of 2K Games.