Irrational's Ken Levine

Yeah... What is more different than a city at the bottom of the ocean? A city that looks like July 4th, 1900. That's the thing that we kept coming back to. It's that idealised vision of the American past, you know when you go to Disney World, that Main Street feeling. That really drove how we wanted the city to feel.

That's quite challenging; it meant a lot for the engine, it's an entirely new engine. We needed a new engine to sell this floating city and these very outdoor environments and this intense sunlight.

I remember the summer, I was outside on July 4th with my camera just getting that... It was exactly that kind of day, that New England July 4th day. There's definitely a feeling to that time of year. There's also an idealised version of that in people's heads: back in the day when people drank lemonade on their porch.

And that's quite different to everything we've done before, where everything is chaos and ruin. We felt we had done that already and we wanted to try something different.

Well, you definitely sense that the scale is very different. You will have these very tight, very traditional BioShock spaces. And then you have these huge things where you're moving at 60 or 80 miles an hour on these sky lines, getting into combats with 15 guys at once.

For me and the team it was about not repeating ourselves. If you look at, whether it's a Final Fantasy where one game in the series is very different to another, or even Alien and Aliens is a great example: two very different stories, one's a haunted house movie and one's an action movie.

For us I think the guiding principle is: if they never stopped making horror movies where everything was a house on a haunted hill with lightning going in the sky, you'd never have The Shining, that antiseptic bright look. How do you create horror in that?

That's what we're doing. We're always trying to challenge ourselves. We've done that, we've done the dark rooms, but that's a crutch, eventually, for a team.

The reason we didn't do BioShock 2 is because... The time frame that game had, and the company understandably wanted another game in Rapture... But we felt we had said what we wanted to say about Rapture, about those kind of environments and that kind of feel.

We want to scare the hell out of people, we want to shock people, but we didn't want to have any of the tools, the crutches, that we knew how to do that with.

I think it's a very talented team, and I think it fulfilled the mission of completing the story of Rapture.

You'll see some similarities and some substantial differences, both in the number of powers and how they're utilised. We definitely want to continue the theme of player expression in how they use their powers and we're expanding on that substantially, both in how you use the powers yourself and how you interact with Elizabeth.

Everything you saw with Elizabeth tonight, all the ways she augmented your powers, that's not a requirement in any of those situations. You could handle all those problems on your own if you wanted to. She's there, she's presenting them, but you don't have to leverage what she does; it's hard sometimes, she presents good opportunities for you, but you don't have to leverage that. That's really important for us.

That's just another facet of the kind of choice you have: all the traditional BioShock tools, more of them, and Elizabeth as well.

And, last thing - sorry, I get excited about this... BioShock was very much corridor, fight two or three guys, corridor, fight two or three guys. When all you have is a hammer, everything looks like a nail. Now, just the scale of the spaces and the number of enemies is going to demand much more of you. Multiple guys at once, guys moving at 80 miles an hour, guys at long distance, all those things will ask different things of the player.

It's another tool in the toolbox for us: these huge, open spaces.