If you’ve already listened to “Serial,” here’s an update on Adnan Syed’s case that we published on Tuesday, Sept. 20, 2022, following breaking news. If you haven’t listened, start episode one below.

A high school senior named Hae Min Lee disappeared one day after school in 1999, in Baltimore County, Md. A month later, her body was found in a city park. She’d been strangled. Her 17-year-old ex-boyfriend, Adnan Syed, was charged with murder, and within a year, he was sentenced to life in prison. The case against him was largely based on the story of one witness, Adnan’s friend Jay, who testified that he had helped Adnan bury Hae’s body. But Adnan has always maintained that he had nothing to do with Hae’s death. Some people believe he has been telling the truth. Many others don’t.

Sarah Koenig sorted through thousands of documents, listened to trial testimony and police interrogations and talked to everyone she could find who remembered Adnan Syed and Hae Min Lee. Sarah discovered that the trial had covered up a far more complicated story than the jury — or the public — ever got to hear. The high school scene, the shifting statements to the police, the prejudices, the sketchy alibis, the scant forensic evidence — everything leads back to the most basic questions: How can you know a person’s character? How can you tell what a person is capable of? In Season 1 of “Serial,” she looks for answers.

It’s Baltimore, 1999. Hae Min Lee, a popular high school senior, disappears after school one day. Six weeks later, detectives arrest her classmate and ex-boyfriend, Adnan Syed, for her murder. He says he’s innocent — though he can’t exactly remember what he was doing on that January afternoon.

But someone can. A classmate at Woodlawn High School says she knows where Adnan was. The trouble is, she’s nowhere to be found.

Their relationship began like a storybook high school romance: a prom date, love notes, sneaking off to be alone. But unlike other kids at school, they had to keep their dating secret because their parents disapproved. Both of them, but especially Adnan Syed, were under special pressure at home, and that stress spilled over into their relationship. Eventually Hae broke up with Adnan.

And then, depending on whom you ask, Adnan was either understandably sad and moping around or full of rage and plotting to kill her.

It’s Feb. 9, 1999. Hae has been missing for three weeks. A man on his lunch break pulls off a road to pee and stumbles on her body in a city forest. His odd recounting of the discovery makes Detectives William Ritz and Greg MacGillivary suspicious.

For instance, why did he walk so far into the woods — 127 feet — to relieve himself? And that’s just the start. A look into the man’s past reveals some bizarre behavior.

A few days after Hae’s body is found, the detectives get a lead that opens the case up for them. They find Jay at work late one night and bring him down to Homicide. At first, he insists he doesn’t know anything about the murder. But eventually he comes clean. He tells them what happened on Jan. 13.

A few weeks later, he’s back at Homicide, and his story has changed. In some ways, these changes are small and understandable. In other ways, they’re big and confounding.

Adnan once issued a challenge to Sarah. He told her to test the state’s timeline of the murder by driving from Woodlawn High School to Best Buy in 21 minutes. It can’t be done, he said. So Sarah and Dana take up the challenge and raise him one: They try to recreate the entire route that Jay said he and Adnan had taken on Jan. 13, 1999.

The physical evidence against Adnan Syed was scant — a few underwhelming fingerprints. So aside from cellphone records, what did the prosecutors bring to the jury, to shore up Jay’s testimony? Sarah weighs all the other circumstantial evidence they had against Adnan, including curious behavior, a disconcerting note and an unexplained midafternoon phone call.

Adnan told Sarah about a case in Virginia that had striking similarities to his own: one key witness, incriminating cellphone records, young people, drugs — and a defendant who has always maintained his innocence. Sarah called up one of the defense lawyers on that case to apply any insight into Adnan’s case and got much more than she had bargained for.

The state’s case against Adnan Syed hinged on Jay’s credibility; he was the star witness and also, because of his changing statements to the police, the chief liability. Naturally, Adnan’s lawyer tried hard to make Jay look untrustworthy at trial. So how did the jurors make sense of Jay? For that matter, how did the cops make sense of Jay? How are we supposed to make sense of Jay?

While Adnan’s memory of that January day is foggy at best, he does remember what happened next: being questioned, being arrested and, a little more than a year later, being sentenced to life in prison.

Adnan’s trial lawyer was M. Cristina Gutierrez, a renowned defense attorney in Maryland — tough, savvy and smart. Other lawyers said she was exactly the kind of person you’d want defending you on a first-degree murder charge. But Adnan was convicted, and a year later his lawyer was disbarred. What happened?

Almost everyone described the 17-year-old Adnan Syed the same way: good kid, helpful at the mosque, respectful to his elders. But a couple of months ago, Sarah started getting phone calls from people who had known Adnan back then.

On Jan. 13, 1999, Adnan Syed was a hurt and vengeful ex-boyfriend who carried out a premeditated murder. Or, he was a bewildered bystander, framed for a crime he could never have committed. After 15 months of reporting, we take out everything we’ve got — interviews, documents and police reports — we shake it all out, and we see what sticks.

When it launched in 2014, “Serial” became a global sensation that has been credited with launching the modern era of audio journalism. The New York Times Company acquired Serial Productions in 2020.

Hosting and executive production by Sarah Koenig; executive production by Julie Snyder; production by Dana Chivvis; line production by Emily Condon; editorial advising by Ira Glass; scoring by Nick Thorburn; scoring and sound engineering by Mark Henry Phillips; mixing for episode 13 by Mike Comite.