Dana Chivvis is one of the producers of Serial, the 12-part weekly podcast that ran through the end of last year and re-examined the 1999 murder of student Hae Min Lee, for which her ex-boyfriend Adnan Syed was convicted. When Serial started in October, the production team were hoping for 300,000 listeners. It has now been downloaded more than 75m times and is the most successful podcast ever. Chivvis, along with presenter/producer Sarah Koenig and producer Julie Snyder, is now researching other stories for Serial’s next series. Our radio critic bumped into her at an industry talk and asked for an update…

Are you still involved in Adnan’s case?

We’re following it, not recording it but following it. There isn’t a whole lot happening right now. Adnan has a hearing, at the June session [of the court of special appeals], which will most likely lead to an appeal, because if he wins then the state will appeal, and if the state wins he will appeal. Deirdre from the Innocence Project is in contact with Sarah about Adnan’s case on and off.

How was it making the show when it suddenly got so popular?

It was weird. We were at the centre of this whirlwind and we were just hunkered down, producing and recording. By episode seven or eight, we were on a schedule: we would do a first edit Friday or Saturday, second edit Saturday or Sunday, third edit Monday, then we would record Sarah Monday afternoon. There would maybe be enough time to eat lunch between the last edit and recording Sarah. The show went up on Thursday morning, so there would be a little time to do pick-ups and finish all the fact-checking, while Julie and our sound designer were mixing the show and scoring it. It ended up being a seven-day-a-week routine.

Facebook Twitter Pinterest Serial has been downloaded 75m times.

How did you feel about Jay Wilds, a major character in the case, who refused to do a recorded interview with you, then did an on-the-record interview with The Intercept after Serial ended?

I wish he had talked to Sarah, but it’s his prerogative to tell his story to whomever he wants. The one thing that stuck in my head about his interview was he changed the location of the trunk pop [the incident where Adnan allegedly showed him Hae Min’s body in the boot of his car]. He says that it actually happened at his grandmother’s house and he hadn’t said that because he was trying to protect her. So that was a new piece of information.

You were obsessive about trying to find the truth. And yet during the series a former detective told Sarah that, in some cases, detectives just want to build a case, not find the truth. Did you find that shocking?

We were completely shocked, this concept of “bad evidence” shocked the pants off us. That detectives might not go and learn some truth in case it didn’t support their theory of the case. I get why, but as a journalist you’re like – No it’s not that I want to find facts to support my theory, I just need to find the facts that tell me what happened.

Cristina Gutierrez, Adnan’s original defence attorney with the unbelievable voice, how did you feel about her?

She made you question your idea of what a trial attorney was, right? Sarah had written about her for the Baltimore Sun, where she used to work. A bunch of clients said Gutierrez charged me this money and then didn’t do what she said, so she agreed to be disbarred. But then people told us, “No, no, no, she was this phenomenal defence attorney, she was one of the country’s best!” It’s an interesting spin on the case. You can’t say Adnan didn’t have a good attorney, because she was really highly recommended, but something happened.

Did you feel pressure when you were making the final episode to reach a conclusion?

I felt a pressure, but Sarah didn’t. What she said is, this is a true story, there’s only one way we could end it. It wasn’t a story we imagined, which would give us a myriad of options, this was all real and this is where our reporting came to, this was the natural ending.

Why didn’t you finish all the shows before you released them?

If we had done all 12 episodes first and released them all at once, or once a week, the show would have had a different patina and we would have lost something in the feel of it. I don’t think it would have affected the sources all that much. But there was this added layer of tension that the audience picked up on, because we were still reporting it, and because we were only one or two steps ahead of the listeners.

What do you think happened in the Hae Min Lee case? Was Jay being intimidated by someone else?

I don’t know. We don’t know. We know that the story that was told is not what happened, but we don’t know much more than that. You can speculate a thousand different ways, and Sarah, Julie and I have done that. I would agree that there is a lot of reasonable doubt about the conviction. Knowing what we know, which is a lot more than the jury knew, there’s too much doubt to have convicted Adnan.

How did you feel about all the Serial parodies, especially the ones from Funny or Die and Saturday Night Live?

We were totally surprised when they aired – especially the SNL skit. We had no idea they were in the works. And while they were both a little cringe-inducing for us, we know that popularity engenders parody. And we’re happy the show has been so popular.

What have you learned from making Serial?

The main thing is that podcasts can be as good as great TV shows, they can attract significant audiences. But moving forward, considering the next stories, this is a new thing we have to take into consideration, this popularity. With our potential sources we say: we have to be fully up front with you, there is going to be a lot of scrutiny and a lot of people watching, and this is your life and your story, so it’s your decision…

So you’ve found your new story? But it’s not a crime story?

We have a few ideas. I can’t give you a hint… We’ve opened it up to anything we’re interested in, and then narrowed it down to a couple of stories. All I can say is that it’s going to be the same TV-for-your-ears, it’s going to be true and it’s going to be fastidiously reported. There’s always going to be a central question too. We will make it sometime in 2015, that’s the goal.

What’s the future of podcasting?

It’s going to follow in the tracks of other digital media evolutions, especially as cars are wired for digital, and as we start thinking of radio as something we can get on our mobile devices. What digital has really done is handed the reins over to the audience, in terms of how they can get and listen to radio (or audio, if you prefer that term). The listener is now in control of scheduling. The format allows for so many freedoms we don’t have on the radio – no time constraints or hard deadlines for example – and that means plenty of room for ingenuity. That’s the spirit from which we created Serial.