In 1999, the body of Hae Min Lee, a popular high school senior, was found in a Baltimore park, a month after she had been reported missing. Lee’s ex-boyfriend, Adnan Syed, was arrested and quickly convicted of the crime. Despite the conviction, Syed has always insisted that he had nothing to do with the murder.

The case, which was closed almost 15 years ago, has become the subject of a new podcast called “Serial,” a spinoff of NPR’s popular series “This American Life.” “Serial” is hosted by journalist Sarah Koenig, with each episode focusing on a different aspect of Syed’s case.

“This American Life” host Ira Glass wrote on his show’s blog that while it follows a real case, he wants “Serial” to have the same effect on listeners as many popular television shows.

“Our hope is to give you the same experience you get from a great HBO or Netflix series, where you get caught up with the characters and the thing unfolds week after week, and you just have to hear what happens next, but with a story that’s true,” Glass said. “Like ‘House of Cards’ or ‘Game of Thrones’ but you can enjoy it while you’re driving.”

Currently in its ninth episode, “Serial” has become a global hit. The podcast became the fastest to ever reach 5 million downloads on iTunes, where it is also the top podcast in the United States, Canada, the United Kingdom and Australia, according to the Wall Street Journal.

In an attempt to capitalize on the popularity of “Serial,” websites like The A.V. Club and  Slate are creating weekly podcasts dedicated to recapping the events of each episode. Funny or Die recently released a mashup of the show’s theme song with Miley Cyrus’ “Wrecking Ball.”

Libby Nelson, a writer for news site Vox, attempts to explain the show’s popularity.

“Serial combines two lowbrow things people love — true crime and high school drama — and does it with NPR-level respectability,” she said. “In other words, ‘Serial’ is ‘Gossip Girl’ meets ‘Dateline’ crossed with ‘This American Life.’”

While fans of the show are speculating that Koenig has a planned ending to the series, one that would include revealing whether or not Syed is truly guilty, she insists, in an interview with New York Magazine, that she is not far ahead of listeners in terms of information about the case.

Koenig warns viewers against expecting closure once the series finishes its first season.

“I don’t know that I’ll ever be at peace with what we find or that there will be a definitive verdict. I’m not going to pick a side just because I’m supposed to for a Hollywood ending,” she said. “But the goal is to figure it out, and I would love to figure it out.”