After your plane crashes into icy uncharted waters, you discover a rusted bathysphere and descend into Rapture, a city hidden beneath the sea. Constructed as an idealistic society for a hand picked group of scientists, artists and industrialists, the idealism is no more. Now the city is littered with corpses, wildly powerful guardians roam the corridors as little girls loot the dead, and genetically mutated citizens ambush you at every turn.