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.