And there are many, many books about real-life murders—about the Boston Strangler, and the Craigslist killer, and the murder of two Dartmouth professors, and on and on. Thinking about production, the most experimental aspect of Serial, Snyder told me, wasn't so much the serialization as it was the idea that Koenig didn't know how the series would end when the first episode aired. The podcast team wondered if people would hear the story and offer information that might influence its outcome. But that's not an unusual approach, either. Just like with an "investigative series in the paper, as you are reporting out the story, more people are going to become aware of the story, see what other people are saying, reach out to you," she said.

So why does Serial feel different somehow?

Snyder says the popularity of the show—and the intensity of listeners's obsession with it—surprised her team. There's something disorienting, she says, about the way the conversation about the show feels akin to the kind of discussion you might find on a subreddit about Lost. Maybe the ethical implications of this kind of storytelling are less McLuhanian—they're not so much about the medium being the message—and more about the cultural context that shapes this moment in broadcast. In other words, maybe it has more to do with the show's listeners than it does with its producers.

Serialized nonfiction in the Internet age means that conversations that might have previously happened around the watercooler are now being published themselves. Which means Serial's audience is producing its own stories full of sleuthing, critique, and conspiracy theories. Slate even recaps the podcast the way it recaps Mad Men.

"That part of it is kind of weird," Snyder said. "I feel like maybe I was really naive... I think all of us are a little taken aback and kind of shocked at the little bit of an attention frenzy. It's a small world of podcast listeners but it does feel like, 'Oh my god. This is a lot more intense than I had ever anticipated.'"

What is it, exactly, that people are participating in here? Are Serial listeners in it for the important examination of the criminal justice system? Or are we trawling through a grieving family's pain as a form of entertainment? These are questions much more easily posed than answered.

What's clear is that a big part of what makes Serial stand out is how relentlessly thorough Koenig's reporting is. (So comprehensive that it's the quality she's lampooned for in this parody.) Koenig makes it obvious in her storytelling that reporting the story ethically—and treating people fairly—is a priority. Some of the thrill in following the story is that listeners are given what feels like a window into her reportorial process—including hints at the bits of info she holds back, whether out of fairness or to ratchet up narrative tension: "I'm going to call this man 'Mr. S,'" she explains in one episode. "I don't want to use his full name for reasons I promise will become clear."