1999 murder fuels world's most popular podcast

It's being called a pop culture obsession. You can't watch it on TV or on Netflix -- you actually can't watch it anywhere. It's like the old days of radio, but on the internet.

The buzz is over a podcast called "Serial" that's investigating the 1999 murder of a teenage girl, and has everyone talking and wondering who did it, reports CBS News correspondent Jan Crawford.

The series focuses on the murder of a popular and gifted 17-year-old Maryland girl, Hae Min Lee. A year after her murder, with no physical evidence, prosecutors convicted her ex-boyfriend, the also smart and well-liked Adnan Syed. He received a life sentence.

"The thing about Adnan is that he never shows his pain, he always hides It," his brother Yusef said.

For 15 years, Adnan and his family have insisted he didn't do it. His mother, Rahman, and his younger brother, Yusef, gave "CBS This Morning" their first TV interview since Adnan's arrest.

"It seems like yesterday. It's hard to think back that I once had a family," his brother said. "It was all taken away."

"Serial" is documenting a real story, and releases an episode every Thursday. It's the brainchild of journalist Sarah Koenig. She often expresses confusion over the case -- allowing listeners to be right there with her in the investigation.

It was at Woodlawn High School in Baltimore, where Adnan Syed and Hae Min Lee met, dated and broke up. Months later, her body was found in some woods. A classmate pointed the finger at Adnan, and Baltimore police arrested the 17 year old at his home.

"They hand cuff him, I say, 'where you taking him?'" his mother recalled. "He say, 'you know he murdered.' I said, 'Wait a minute.' [They said] that he killed the girl, you know, and I said, 'Wait a minute, why are you taking him like this?'"

Serial's popularity has sparked a devoted online following gathered around the internet's equivalent of a water cooler after each episode, debating Syed's conviction.

David Carr is the media columnist for the New York Times, who has examined why the show -- no bells and whistles, just gumshoe reporting -- is striking such a chord across America.

"Well it's kind of as old as story telling itself, right? We go back to as Edgar Allan Poe or Charles Dickens; people love serials, people love cliffhangers, people love whodunnits," Carr said.

For Syed's family, the overwhelming response has been a blessing -- and a struggle.

"These are real people, there are real victims," Yusef said. "There is a real girl who died."

Every week, Syed's mother and brother listen to the podcast. Like the general audience, they never know the plot of the new episode before it airs.

"Sometimes [we] listen at 5am or 6am, as soon as they put it on," his brother said. "And some days I will be like, 'Oh this is a really great episode.' And some days I'll feel so down and depressed."

The podcast has had a broader impact. The non-profit group The Innocence Project, has taken on Adnan's case, giving his family new hope after 15 years.

"We are just so thankful that the story is out there," Yusef said.

Sarah Koenig and her team are still reporting the story, planning several more episodes after Thursday's release. Meanwhile, Adnan is pushing forward with an appeal.