After introduces Tessa Young, a high school graduate who’s just about to start her first day at Washington Central University as an undeclared economics major. On the day of her move-in, she’s accompanied by her caring yet rather controlling mother, Carol Young, and her high school sweetheart Noah Porter. Upon her arrival, Tessa is greeted by Steph Jones, Tessa’s roommate, and her girlfriend, Tristan. Unlike the studious Tessa, Steph and Tristan are all about the party scene. Nevertheless, Tessa gets along with her new friends and settles down at her dorm.
Steph invites Tessa to a party at a frat house, to which she reluctantly agrees. There, Tessa gets to know the rest of Steph and Tristan’s clique, which just so happens to include Hardin Scott, a mysterious boy she met in her dorm room. The group suggests playing Truth or Dare, and Tessa is dared to lock lips with Hardin. She bluntly refuses and escapes the party, accidentally wandering around Hardin’s house. Hardin suddenly enters and the two share a lingering moment before Tessa snaps out of it and leaves.
For the next couple of days, Hardin persuades Tessa to come with him to a lake house. Before they know it, the two start flirting with each other and eventually kiss in the water. But the passion doesn’t last long, and later on, in the movie, it’s become apparent that Hardin is adamant about the idea of dating. Heartbroken, she continues to ignore Hardin, but her heart softens after Hardin gets himself into an emotional outburst at home.
Despite her friends’ warnings to take things slow with Hardin, Tessa doesn’t listen to them and continues a seemingly perfect dating life with him. Everyone is always telling her that Hardin is up to something. Although she ignores them at first, Hardin, under the pressure of his friends, finally confesses to Tessa that Hardin is dared to make Tessa make fall in love with him and break her heart in the end. Tessa realizes that her relationship with Hardin is just one big lie.
After spending some time at home, she returns to university and applies for an internship at Vance Publishing. She spends more time in her classes. On the day of her English paper essay submission, her professor puts her aside and gives her an essay Hardin submitted, which sounds like it’s meant for Tessa. After class is dismissed, Tessa and Landon sit on the campus lawn. She reads the essay, which happens to be a letter from Hardin professing his feelings for her.
After We Collided starts off with Hardin dreaming of Tessa, only to wake up all alone in his car, upset that Tessa hasn’t been replying to his texts. As he exits his car, a homeless man who is desperately looking for someone abruptly approaches him, prompting Hardin to shoo him away. Meanwhile, at Vance Publishing, Tessa begins her first day as a bright intern. However, things go down south after an awkward encounter with her new co-worker, Trevor Matthews. Tessa is immediately welcomed by secretary Kimberly (who is revealed to be Vance’s romantic interest), and Christian Vance, the founder of Vance Publishing.
One night, Tessa attends a nightclub with her co-workers to pique a potential investor’s interest. However, after too many drinks, things got hot and heavy. From dancing with strangers to one accidental kiss, Tessa, in her drunken stupor, calls Hardin and gloats about how much she’s having now. Trevor suddenly finds her and the two return to their hotel room. Tessa accidentally spills her wine onto Trevor’s clothes and asks him to undress, so she can wash off the stains. All of a sudden, Hardin storms into the room, angry at a half-naked Trevor and cursing him out of the room. The pair’s rage doesn’t last long, and eventually, the two sleep with each other.
But their peaceful reunion doesn’t last long. Tessa soon comes to terms with the complicated mess that is in her work life and comes to terms with her true feelings for Hardin. Things get even more complex with Hardin’s family coming into the mix, with his mother Trish Daniels suddenly visiting him in the States and befriending Tessa. Tessa also goes on a venture searching for her long-lost father, who appears in the ending in the most surprising way possible.
In After We Fell, Tessa and Hardin are now happily living together, but deep down, they’re still incredibly insecure about themselves. Tessa receives an offer to work for Vance Publishing at their Seattle office. While she’s excited about the opportunity, Hardin doesn’t share the same sentiment. He’s afraid that their long-distance relationship wouldn’t work and more trouble ensues. Also, it doesn’t help that Hardin initially wants to bring Tessa to London after graduation.
Despite this, Tessa takes up the opportunity to move to Seattle. The jealousy-ridden Hardin becomes incredibly jealous, especially since she’ll be in the same city as Trevor. Meanwhile, Tessa has other struggles to tend to; she’s trying to reconnect with her estranged father, whom she has not seen for nine years. Hardin, originally reluctant about Tessa meeting her father for fear of getting hurt, finds himself bonding with the man as they bond about their alcoholism.
Everything seems smooth sailing until Hardin takes Tessa to London for his mother’s wedding. He is hesitant at first because he’s scared that Tessa will judge his past and origins. With Vance’s encouragement, Hardin invites Tessa to his mother’s wedding. Things appear fine, but the happiness is short-lived. The night before his mother’s wedding, Hardin accidentally encounters Vance having sex with his mom. Kimberly finds out about Vance’s cheating ways and is furious with him. Things take for the worse when Vance reveals to Hardin a long-lost secret.