At sixteen, Lara Jean Song keeps her deepest secrets tucked away in a hatbox—love letters she's written to every boy she's ever loved, letters that were never meant to be seen. They're her safe haven, her private confessions she could never dare to share.

But what happens when those letters are mysteriously mailed out? Suddenly, Lara Jean's quiet high school life spirals into chaos as her secret crushes confront her one by one. Friendships are tested, reputations are on the line, and her heart is more exposed than ever before.

Will Lara Jean find the courage to face the mess she's created, or will she watch her world crumble around her?