As the school mourns the death of Hannah Baker, her friend Clay receives a box of tapes with messages she recorded before she committed suicide.

Hannah makes friends with Jessica and Alex, two other new students. Justin doesn't show up at school, and Hannah's mother finds something troubling.

Jealousy and gossip take a toll on Hannah's relationships. As Alex struggles with feelings regret, the guys pressure Clay into getting drunk.

Another student sabotages Hannah during a class project. Clay's nightmares about Hannah spill over into the daytime.

Tyler goes out with Cyrus's sister. Chloe confronts Bryce about the tapes. Jess wonders if she's ready to date again. Mr. Porter wrestles with regret.