Back in 1995 I gave a lecture at the Computer Game Developers' Conference in which I identified several problems with interactive storytelling. I reprised those ideas a few years later in a Designer's Notebook column called Three Problems for Interactive Storytellers. At the end of both the lecture and the column, I suggested that instead of trying to tell stories, we should build worlds in which stories can happen -- worlds in which players live a story of their own creation. The industry didn't have a term for it at the time, but what I was proposing was sandbox storytelling.
In sandbox storytelling, the idea is to give the player a big open world populated with opportunities for interesting interactions. The player isn't constrained to a rail-like linear plot, but can interact with the world in any order that he chooses. If the world is constructed correctly, a story-like experience should emerge.
Not everybody thinks sandbox storytelling is a good idea. The year after I gave my lecture, Bob Bates gave his own lecture at the 1996 CGDC called "The Responsibility of the Author."
One of the things he said was, "[Open-ended environments] may be fun to explore, but they do not fulfill the obligations of a story. There is no beginning, middle, or end. There is no pathos, no human drama, no greater truth to be gleaned from the hard-fought battles that the characters wage."
Bob recommended that we use a linear series of open environments instead -- what we now call a multilinear or foldback story, in which the player is compelled to go through certain choke points in the plot line.
However, Bob was assuming that in an open-world environment the player would have to go find the plot, and all she would get is a disconnected series of events. I think Bob was expecting that the plot events would be tied to specific locations, and if the player could experience them in any order, they would have to be unrelated to each other.
I'm not surprised that he made that assumption, especially back then. We're very used to mapping plots onto physical locations -- so much so that it's our default approach, and any other system is unusual. From Zork to Half-Life to Fallout 3, movement through space equals movement through the story. But to do sandbox storytelling, we have to get rid of this notion and think instead about how to create a plot that advances -- and maintains its continuity -- by other means.
The Grand Theft Auto games famously include sandbox play, but they don't do sandbox storytelling. Instead, you get the usual linear chain of missions; complete one and you get another one, and so on. It just so happens that the missions take place in a large open world, and you can abandon the mission and just wander around wreaking mayhem (or driving a taxi) if you want to.
Grand Theft Auto IV
In a way, this was what Bob meant by a linear series of open environments, except that instead of a series of different environments, the Grand Theft Auto games just give you new missions in the same environment -- although you do unlock new areas from time to time.
The Sims offers sandbox storytelling after a fashion. It gives you a world with a lot of stuff in it, and simulated people with varying personalities. As the player, you can make them interact and generate a (somewhat) story-like experience. Because the Sims don't speak English, most of the storytelling goes on in your head, but that's all right. You can make your own machinima, caption or record voiceover for it, and upload it to YouTube.
But The Sims uses a multipresent interaction model in which you don't have a particular avatar within the game world. To get a story out of The Sims, you have to manipulate more than one of the characters, rather than role-playing a single character. This makes you more of a creator than a participant. That isn't the way most storytelling games work, and I don't think it's what most people want from a storytelling game.
Computer role-playing games give the player a big open world, but rather than providing a single story, the world is full of quests -- essentially, disconnected subplots. I love Western RPGs, but they don't have quite the same feeling as a story with one plot. They're more like the legends of Hercules, or any other ancient hero who appears in several unrelated stories.
So how do we make an open-world game in which the player can roam around, yet still feels as if he's taking part in a story? First, as I said, we have to abandon the idea that the player will experience the plot entirely through exploration.
At the same time, traveling still has to be an integral part of the story; otherwise the travel will just be tiresome. Movies usually cut out travel time -- somebody comes out of their house in the morning, gets in their car, and in the next shot they're walking into their place of work -- unless the movie is actually about travel, as in a chase movie.