Teenager Clay Jensen returns home from school 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 committed suicide two weeks earlier. On tape, 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 a package is one of the reasons why she killed herself, and after each person has completed listening to the tapes, they must pass the package on to the next person. If anyone decides to break 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 inevitable suicide.