Lauren Fox works as the bookkeeper at Cold World, a winter-themed tourist attraction in a converted warehouse in Orlando, Florida. The attraction features the Snow Globe, an enclosed area with real snow, an ice skating rink, and Wonderland Walk, a lane of vendor stands. Lauren is methodical and reserved, and she harbors a crush on Daniel Alvarez, the vice president and son of the owner, Dolores.
Her main source of friction is Asa Williamson, a longtime employee with tattoo-covered arms and aqua-blue hair who has worked at Cold World for ten years. Asa teases Lauren constantly and lives with several housemates, including Kiki, one of Lauren's closest friends. Lauren has felt off-kilter around Asa since her first week, when she vented to a stranger at a holiday party about wanting to cancel Secret Santa, only to discover the stranger was Asa, who had organized it.
At the annual staff meeting, Dolores announces that Cold World has grown stale and tasks Lauren, Asa, and Daniel with each developing a proposal to revitalize the attraction. Asa suggests they collaborate, but Lauren refuses. During this period, Asa casually reveals he is bisexual by mentioning past boyfriends, and Lauren takes the information in stride.
Away from work, Lauren begins volunteering as a guardian ad litem, a court-appointed advocate for children in foster care. She is assigned to Eddie, a nine-year-old boy. The role connects to Lauren's past: Her mother lost custody of her at age nine due to drug addiction and died of an overdose less than a year later. Lauren grew up in foster care under a caretaker named Miss Bianca. She struggles to connect with Eddie but is determined to be honest with him, even when he asks when his mother is coming and she can only answer that she doesn't know.
Asa convinces Dolores to have Lauren work a shift in the Snow Globe, ostensibly so she can learn other roles but really to throw her off balance. When a rude customer harasses Lauren, Asa intervenes, then dismisses her back to her office. Frustrated, Lauren dumps snow down his neck, sparking a snowball fight that earns them a reprimand.
Lauren returns to Cold World after hours to print a report for Daniel and enters through a propped-open back door, closing it without realizing it will trigger the alarm if reopened. Asa, who stayed late to repair a broken snow machine, discovers they are locked inside until morning. Trapped together, they play a conversation game Asa invents, with prompts like "Tell me a secret" and "Compliment me." As the game strips away their defenses, Lauren asks why Asa didn't kiss her under the mistletoe at the previous year's party. He says he didn't think she wanted him to; she admits she did. Asa kisses her, and the encounter escalates into physical intimacy. Afterward, Lauren panics and asks him to keep everything secret. They slip out separately the next morning.
Over the following days, their attraction intensifies despite Lauren's resistance. She wins a date with Daniel in a gift-wrapping contest, but her attention drifts to Asa. When she visits his room one evening and they begin kissing, Kiki walks in. Lauren spirals, dismissing what happened between them as casual. Asa, hurt, walks her to her car in silence.
They reconnect when Lauren brings Eddie to Cold World for a supervised visit with his mother, who fails to show. Asa teaches Eddie to skate while holding Lauren upright on the ice, and Lauren opens up to Eddie about her own time in foster care.
At the holiday party, the Secret Santa exchange goes awry: Lauren traded away Asa's name, while Asa traded to get hers but could not bring himself to give the meaningful gift he made, sticking a bow on a half-used bottle of car coolant instead. Daniel corners Lauren and makes crude remarks about her body; she calls his behavior harassment. Lauren performs a raw karaoke rendition of "Blue Christmas," pausing to deliver a monologue about feeling like an outsider in Cold World's family. Asa leads her to the Snow Globe, where he has rigged the old machine to produce falling bubble snowflakes, the magical effect she once wished for. He drives her home, and she asks him to stay. In bed, she tells him about her childhood and her fear that people will leave if they know her past. Asa shares his own experience: His father, a pastor, kicked him out at 17 after learning Asa had kissed a boyfriend. They fall asleep holding each other.
The next morning, Lauren pitches a collaborative proposal: an interactive educational exhibit paired with Asa's mural art for the Snow Globe and new programming. He agrees, and they have sex for the first time. They attend his sister Becca's baby shower, where Asa's estranged parents unexpectedly appear. Lauren stands up for him, telling his father that being with a woman does not make Asa any less bisexual. Asa tells his parents directly that they hurt him by rejecting him. Afterward, he and Lauren become an official couple.
They spend a blissful week together, though Lauren insists on keeping the relationship secret at work. On Christmas morning, Asa gives Lauren a repurposed school-photo frame filled with his illustrations of the good-luck flowers she and her mother once shared: a rose for first grade, a lotus for second, violets for third, and an iris for fourth. Overwhelmed, Lauren tells Asa she loves him. He says he loves her, too.
At the post-Christmas presentations, Dolores praises their proposal but reveals she has been speaking with an investment group about selling Cold World. Lauren volunteers to go part time and mentions she has been accepted into a master's accounting program, information she never shared with Asa. Blindsided, he walks out. When Lauren follows, Asa says he cannot keep hiding their relationship. Lauren misinterprets his words as a breakup and shuts down, telling him they only dated for a week. They part in pain.
Days later, Kiki intervenes, explaining that Asa meant he wanted to stop hiding, not stop being together. She tells Lauren that people want to show up for her, and she has to let them. Lauren throws a New Year's Eve party at her apartment as a gesture of openness. Asa's housemates bring him without telling him whose party it is. Lauren pulls him aside and apologizes, admitting she assumed rejection was inevitable. She tells him she loves him and no longer wants to hide. Asa tells her he has loved her since the first holiday party. They reconcile.
In an epilogue set almost a year later, Lauren has moved in with Asa and his housemates, works part time while pursuing her master's degree, and continues as Eddie's guardian ad litem. Asa has left Cold World to work at a local LGBTQ services center and sells his art, including commissioned murals. At the annual holiday party, he takes Lauren to the Snow Globe to reveal his completed mural, a vintage postcard design with details including a rosebush with a fox curled in front of it. When she turns back to him, he is on one knee with a ring. She says yes.