Content Warning: The following summaries and analyses contain discussions of suicide and sexual assault.

A high school student, whom readers later learn is Clay Jensen, mails a shoebox of audio tapes to Jenny, the next person on a list of 13 people. Clay received the tapes himself the day before and listened to them throughout the night. The tapes are narrated by Hannah Baker, a girl in his school who died by suicide. Clay wonders if he should have waited to mail the tapes to Jenny but decides that she does not deserve any extra time of peaceful ignorance based on what she has done. Clay wonders if others on Hannah’s list kept their post office receipts as gruesome reminders, but Clay does not keep his receipt: He does not need it to remember Hannah’s story. Her voice is stuck in his head, and familiar locations around town will be reminders enough. Clay feels physically ill at the thought of going to school and seeing his first period teacher, Mr. Porter—the last name on Hannah’s list. He also dreads seeing Hannah’s vacant seat.