In BioShock, you take on the role of an average guy who's constantly finding himself put in weirder and more troublesome situations. Your plane has crashed over the ocean, you survive, and in your panic and bewilderment, you see a strange buoy. You swim over to it, and it leads you down to a brilliant underwater city that's suffered a colossal war, and it's on the brink of collapse. What helped cause the war was a genetic chemical that scientists discovered could enhance people to do extraordinary things -- far beyond normal capacity. But along with the great physical enhancements come horrific psychological ones.

For us, we wanted to have…we knew we had this theme of biological experimentation. That was at the heart of where all the players' powers and all of the creatures from the game came from. From this biological intentional mutation I wanted to build a world where that would happen and be believable and not in the far future, but something that we could speak to, like something we're dealing with now -- with stem cell research and the moral issues that go around. And I have my useless liberal arts degree, so I've read stuff from Ayn Rand and George Orwell, and all the sort of utopian and dystopian writings of the 20th century, which I've found really fascinating.

We had a similar vibe in System Shock 2 where, you know, the monsters -- and people weren't sure if it was going to work at the time -- but you would get a real sense of the monsters' humanity. You would find logs of them, where they would take you through the process turning from a human into something less or something more, depending on how you look at it. In BioShock, we're really taking that to the next step with that. We have actually been through some transitions in this. Originally, we just sort of made the monsters sort of "monstery" looking. And as they change they become more and more… Well, they're just sort of like you; they're people in their clothes in the period. Like the guy working at the docks and a woman working at a bank, an accountant, and an athlete. In other to survive the terrible events that happen here, these people start modifying themselves genetically, through the same techniques you are, and get a lot of the same powers you do. In order to survive, they get less and less human. You see that and you hear about that, and you observe that, and it brings you close to them and those experiences are the ones we try to bring you close to because they parallel your experiences, and you're becoming less human, and we want to make that feeling meaningful to the player.

I've always said that, when we were working on Thief, I'd rather have a story element about the moss arrow then about some cult you never get involved with in the game or some god or something. That's because I play with the moss arrow, it's part of my game experience; I want to tie that into the story. The same way here, the story is about people going through the same thing that you're actually going through in the game, as you modify your body and change it, and become something less or more than human. There are a bunch of other tools we have involved how we balance the game, what the resource economy is like, and how powerful you feel, and how deadly combats are. Those are all elements that go into it. The mood and the vibe are critically important.​