Teenager Clay Jensen returns home from school one day to find a mysterious box lying on his porch. Inside, he discovers seven double-sided cassette tapes recorded by Hannah Baker, his classmate and unrequited love, who tragically took her own life two weeks earlier. On the tapes, Hannah unfolds an emotional audio diary, detailing the thirteen reasons why she decided to end her life. Her instructions are clear: each person who receives the package is one of the reasons why she killed herself. After each person finishes listening to the tapes, they must pass the package on to the next person. If anyone breaks the chain, a separate set of tapes will be released to the public. Each tape is addressed to a select person in her school, and details their involvement in her eventual suicide.