How did Telltale's The Walking Dead, an episodic action-adventure adaptation for the gorey comic book and cable TV series, become the fastest-selling title in the developer's eight-year history? Some would immediately point to the popularity of Robert Kirkman's zombie franchise -- it's long been a favorite amongst comic book fans, and the AMC show continues to pull in huge ratings. The Walking Dead is one of the hottest properties right now, so it's no surprise people are flocking to a game based on its license. But Telltale has worked on plenty of tie-ins for big films and TV shows before like CSI, Back to the Future, and Law & Order. None of those games had anything like the success of The Walking Dead, which has already sold over a million episodes (70 percent of those for Episode 1: A New Day). And that's after releasing just the first episode of the five-part series; Episode 2: Starved for Help ships for PC and XBLA/PSN later this month. There's more to crafting a hit like The Walking Dead than picking up a well-known name, the game's story consultant and screenwriter Gary Whitta (The Book of Eli) tells Gamasutra. He stresses that Telltale sought to play to the strengths of the series' story -- which is just as much about dealing with conflicts between the living as it is about surviving the undead -- to create a game that would meet players' narrative expectations. "[The setting] is just a great forum for human drama because it reveals people for who they really are," says Whitta. "People's true natures emerge. The hero and the villain exist inside every one of us. You often don't see the extreme versions of those personalities in our comfortable world where there's not really a lot of drama around day-to-day. "But when you strip civilization away and people are fighting for their lives, and the lives of themselves and their loved ones are on the line, people really kind of emerge as kind of amplified true versions of themselves. So, it's a great way to create these very extreme human dramatic moments. They gave themselves a great foundation to start from." Though Telltale's game features an original story with its own cast separate from the comics and show (with some cameos), it's managed to attract and appeal to the franchise's fans by emphasizing the drama between characters, and forcing players into making life-or-death decisions. So it's not entirely about blasting off the heads of zombies with shotguns -- though there are certainly portions of that.

Matching story-based design with emotional moments

Understanding that it needed to emphasize the toll a post-apocalyptic zombie-filled world would take on survivors, the Walking Dead team decided on "a design approach that was very heavily focused toward story -- less worrying about creating puzzles and traditional graphic adventure game-type elements, and more about creating an almost interactive TV show," says Whitta. He adds, "I think a lot of the player choices and a lot of the moments that really resonate with players are less about kind of the classic intellectual puzzles of traditional video games like 'How do I find the key that opens the safe?', and more about 'Am I going to let this person live or die?' or 'Who am I going to side with in this very difficult situation where there's not really any correct answer?'" Whitta argues that this kind of approach allowed the group to create a more accessible title that could attract broader audiences compared to typical adventure titles. The appeal of making meaningful decisions that impact the story and other characters in a big way can be much easier to convey to others than the satisfaction of solving a tricky puzzle. "I think [we're] engaging a part of the brain that is not typically used when people play games, because games haven't been very story- or character-driven," he says. "They haven't been really driven by emotional concerns. They're usually driven by these very kind of logical, pragmatic concerns. 'How do I solve this challenge? How do I move forward?'" But he believes that more studios are making efforts to offer emotionally engaging experiences in their games, and opportunities to feel the weight of their choices. Whitta praises BioWare as one of the developers that's really designed its games with this in mind -- he mentions a devastating Mass Effect 3 moment when one of his choices to save one alien race resulted in the extinction of another (his favorite race in the game, no less). "I think that's going to be a bigger developer target," he predicts. "I think the whiteboards in development offices are already starting to look very different. I think the questions on the boards are more like 'How do we emotionally engage the player?' rather than 'How do we intellectually engage the player?'" says Whitta.