Hitman Absolution director Tore Blystad faces a lot of challenges with the latest game in the franchise. The team has built an entirely new engine, Glacier, to power it. The believable environments it allows the team to craft, ironically, make the game - out later this month - more difficult to develop.

When your game is about sneaking through a realistic world, the things that aren't realistic stand out just that much more. And as all game designers know, there's another source of tension there -- because what's realistic is not necessarily fun.

In this new interview, Blystad explains how he and the team at IO Interactive have approached everything from players' expectations to be spoon-fed a completely linear play experience, how they've dealt with the challenge of making realistic but not too realistic AI, and what "immersion" really, in the end, means.

Has it been hard to keep the franchise fresh for you, as a developer, over the years? How many installments have there been? Five?

TB: This is the fifth one.

That's a lot of games.

TB: Yeah. It's been quite challenging, also, because as an artist producing the Hitman games, it's a different type from other games, because it's usually civilian scenarios of different kinds. Because military bases and these kind of very heavily guarded areas, it becomes less of a challenge in a game where you're choosing so much what to do by yourself. So coming up with these different scenarios, and different kinds of unusual ways of approaching a kind of familiar area, is something that is increasingly difficult for us, since we've gone through so many in the past.

When this franchise started there was a lower level of character nuance expected out of protagonists. At that time, you could pretty much just be a bald guy with a gun, and that would be the beginning and the end of what you needed to convey. Have you found that that's been a challenge?

TB: Yes, absolutely. That's why I would say there's probably 10 times more work going into this game than any other Hitman game in the characterization -- not only of Agent 47, but also of the other characters in the world. And since the AI is so, I would say, "complex", it has to be able to react to anything you can do as a player. Every character has to have... I don't know, there's like hundreds of different responses they need.

So just the complexity of that, and recording this, with like two thousand pages of dialogue for the game... it becomes a big logistic problem as well, because it's simply so much content you need to produce to create the diversity you need for a living, breathing world. We've seen the need, of course, to expand our skill sets, and hiring in experts in different fields -- like cinematography and film direction -- to get a more cinematic feel to it.

I wanted to talk about the AI, actually, because I spoke about this before when I interviewed your technical lead, Martin Amor. Where does the AI begin and the game design end? How do you tackle that?

TB: It's very difficult for us, because it's like the chicken and the egg in a way. Because we want a lot of diversity with the AI, and we also want a lot of responses, but we are not really sure if it's going to work until we actually try it out. And just trying something that feels believable is extremely expensive -- with all the mo-cap you need, all the voice recordings you need, all the context within the world -- to come to a point where someone can sit down that is not on the team and judge it for themselves.

So it's been a lot back and forth between level design, and game design, and technical design, to come up with something that we believe can tackle anything you do in an interesting way, and not just kill you instantly. Because it's very much about the player pushing the game, and the game pushing back, instead of just using a sledgehammer and just killing you instantly, and then restarting.

Because we really want, in Absolution, the feeling that you could try and you could fail, and then you could improvise from there and try something else. Yeah, there's some lines you cannot cross. If you start just killing everybody, of course the AI will be pretty upset, and they will start looking for you if you run away, and they will look for a really long time depending on how bad you were.

But if you're just doing simple things like trespassing into an area, they will kindly try to get you to leave the premises, and if you continue to egg them on, they will get continuously more irritated, calling on their friends. And this kind of playfulness within the AI is something that we believe is very important in a game like Hitman, where it's so much about your experience, and you trying to find your own way -- your own kind of way of solving the game.

And this is something that is also... it's quite difficult, actually, to educate players that this is what the game is trying to serve you, because people are increasingly used to games where you're told to do one thing, and if you stray from this line, there will be nothing else around. It's like, you have this experience, and that's it. So we're telling people, actually, "No, no, no. You choose by yourself."

If you want to go in here, or here, or if you want to kill them or not, it actually changes the way you play the game -- when you understand that you have the choice. So in the first couple of levels, we are continuously working [on it]. And still back in Copenhagen we're trying to find out, are we teaching the players everything that they need to understand about the gameplay and the possibilities of the game?