Hannah Cho and Nick Cooper have been best friends since 8th grade. They talk for hours on the phone, regularly shower each other with presents, and know everything there is to know about one another.

There's just one problem: Hannah and Nick have never actually met.

Hannah has spent her entire life doing what she's supposed to, but when her senior year spring break plans get ruined by a rule-breaker, she decides to break a rule or two herself. She impulsively decides to road trip to Vegas, her older sister and BFF in tow, to surprise Nick and finally declare her more-than-friend feelings for him.

Hannah's romantic gesture backfires when she gets to Vegas and meets Nick's girlfriend, whom he failed to mention. And it turns out his relationship status isn't the only thing he's been lying to her about. Hannah knows the real Nick can't be that different from the online Nick she knows and loves, but now she only has one night in Sin City to figure out what her feelings for Nick really are, all while discovering how life can change when you break the rules every now and then.