When Brooklyn sees her boyfriend, Heath, making out with someone else at a New Years party she breaks up with him and leaves the party. She gets lost and eventually runs into the charming Harry Styles. But Brooklyn isn't looking for a relationship. So she decides to be friend with him. She sets up a series of rules for her about who she can date so she won't get hurt. Rule number one, no dating friends, including Harry. But rules are meant to be broken, right?