The first season of Serial contains 12 episodes.
Released in 2014, Serial’s first season investigated the 1999 murder of Hae Min Lee and the conviction of her former boyfriend, Adnan Syed. Host and journalist Sarah Koenig revisited witness accounts, phone records, school schedules, police evidence, and competing interpretations of the case.
The season used a serialized structure: each episode developed the same investigation rather than presenting a separate case. That approach helped distinguish Serial from anthology-style true-crime programs and encouraged listeners to debate the evidence as new details emerged. The season finale, “What We Know,” was episode 12.
The number is sometimes confused with the total number of episodes in the podcast’s first several seasons. Later seasons covered unrelated subjects and had different episode counts. Season two examined Bowe Bergdahl, while season three explored cases within the American criminal-justice system. Thus, 12 refers specifically to season one, not to the entire Serial catalog.