Seventeen-year-old Caroline Wexler, Kat Dennings, leaves the chaos of city life behind to move to a small town, where the lingering smoke from an industrial fire casts a heavy shadow over its inhabitants. As she settles into her new high school, Caroline faces a sea of students who seem trapped in a fog of apathy, their gazes distant and devoid of passion. It's in this stifling environment that she catches the eye of Thurston Goldberg, Reece Thompson, a charming and friendly classmate who quickly becomes infatuated with her. Their first meeting at a party sparks a complex emotional journey for Caroline, as she finds herself captivated not only by Thurston but also by her charismatic high school English teacher, Mr. Anderson, Josh Lucas.
With Halloween on the horizon, Thurston’s friends—Paul, [Landon Liboiron], Charles, [Jesse Reid], and Craig, [Calum Worthy]—spend the day lost in a haze of indulgence, leading to a harrowing incident during health class when Craig suffers a violent seizure. Following this event, Mr. Anderson cancels a planned meeting with Caroline to assist Ms. Budge, [Rachel Blanchard], her health teacher, which leaves Caroline feeling rejected and emotionally vulnerable. Amidst the chaos, she finds herself drawn back to Thurston, culminating in an intense night shared in her car. Thurston reveals that he had been a virgin until that fateful evening, deepening their connection.
In the subsequent days, Mr. Anderson attempts to reignite their relationship, but only under the shroud of secrecy. Caught between her affection for Mr. Anderson and her evolving feelings for Thurston, Caroline is also troubled by a rising fear in the community due to a serial killer targeting high school students, which is the focus of alarming reports on KCRR.
As the bond between Caroline and Thurston becomes more profound, Mr. Anderson's mental stability begins to falter, endangering the foundation of their tangled relationship. In a shocking twist, he reveals that his charming persona was all a deceptive front designed to hide his true motives. The precarious balance crumbles as Thurston, now privy to the truth, makes the devastating choice to break away from Caroline. Her departure leaves Mr. Anderson on the verge of a breakdown.
Desperately seeking solace, Caroline turns to her former lover, only to be confronted with the pain and turmoil that now envelops Mr. Anderson. His catastrophic spiral culminates in an accident when he accidentally shoots himself in the leg, a cruel reminder of the fallout from his choices. Meanwhile, Caroline maneuvers through the wreckage of their love, leaving a poignant note for Thurston, urging him to stay at the Christmas party, where she intends to reclaim their bond.
In an additional storyline, Thurston's emotional rawness is preyed upon by Jenny, [Katie Boland], who harbors an unhealthy obsession with him. As Caroline inadvertently encounters the now-deceased serial killer, her actions are mistakenly viewed as heroic, leading to a reunion with Thurston. The situation takes an ironic turn when Ms. Budge confronts Mr. Anderson, bearing grim news about the serial killer and taking him to the hospital to care for his injured leg.
