You could tell Ms. Koenig has often thought that Mr. Syed is probably innocent, or at a minimum, received from his lawyers a halfhearted defense. She came to like him, and so did we. But as she put it in one episode, “What if he is this amazing psychopath, and I’m getting played?”

The soul of “Serial” has been in the way Ms. Koenig has done her digging so transparently, airing niggling doubts along the way. She’s incorporated new evidence, sometimes from people who called her only after having their memories jogged by the most recent podcast. As she has moved along, she has uprooted the way murder mysteries are usually told. She’s allowed us to feel like Harper Lee, riding shotgun with Truman Capote as he reported “In Cold Blood,” before he conveniently mangled facts in his telling.

“Serial” plowed up entire fields of odd detail for listeners to linger over. The man who discovered Ms. Lee’s partly buried body, a potential suspect who is referred to as “Mr. S.,” turned out to have a penchant for streaking. A phrase that popped out of the mouth of the “Serial” producer Dana Chivvis during a re-enactment of a crucial event — “There’s a shrimp sale at the Crab Crib” — became a tasty Internet meme. I made the mistake of Googling the phrase, and now T-shirts bearing the slogan follow me across the Internet. At the conclusion of the final episode of “Serial,” Ms. Koenig, channeling Henry Fonda in “12 Angry Men,” remarks that, “As a juror, I have to acquit Adnan Syed.” Yet she’s a journalist, not a juror. She adds: “So just as a human being, walking down the street next week, what do I think? If you ask me to swear that Adnan Syed is innocent, I couldn’t do it. I nurse doubt.” Many will listen and conclude, “They got the right guy.”

“Serial” has demonstrated the bedrock truth of Calvin Trillin’s assertion in his book “Killings” (1984) that “when someone dies suddenly shades are drawn up.” A murder “gives us an excuse to be there, poking around in someone’s life.” The human details tend to be why we’re there. They’re what resonate, even if the whodunit elements never catch fire.

Endings aren’t as important to me, in terms of fiction at any rate, as they are to many people. (I’ve had mighty arguments on this topic with friends.) If a writer has kept me hooked on a long westward cross-country drive and blows a tire at the Nevada-California border, I rarely hold a grudge. I bail out on most writers back in Scranton.

This is a way of saying that no matter how “Serial” stuck its landing, I had decided by Episode 3 that I would follow Ms. Koenig’s work wherever it took her. She is an agile writer of cool, declarative sentences. Her voice — literate, probing, witty, seemingly without guile — is an intoxicating one to have in your head.