Two socially awkward high school seniors, Seth and Evan, have been best friends since childhood and are on the cusp of going to separate colleges. When a girl named Jules invites Seth to a party at her house, the evening becomes a chaotic test of their friendship and their willingness to push boundaries. Their dorky friend Fogell schemes to score alcohol with a fake ID under the moniker “McLovin,” and Seth promises to buy Jules a few drinks to help him impress her. Concurrently, Evan crosses paths with his own crush, Becca, and offers to grab drinks for her as well, hoping to keep the night alive.
Fogell’s fake ID moment initially seems successful at the liquor store, but trouble erupts when a robber knocks him down right as the purchase is about to go through. Outside, a mistaken encounter with the police leads Seth and Evan to believe Fogell is being arrested, and Seth argues that Fogell should face the consequences alone—even though he was pushed into the plan by their friendship. A motorist who stops to help after the crash offers a deal: he’ll take them to another party where alcohol can be obtained if they wordlessly agree not to report the incident.
Meanwhile, the police ultimately drive Fogell to the party, and, despite being on duty, the officers join in the drinking and quickly bond with him. The prospect of smooth sailing for Fogell’s alcohol run fuels the trio’s reckless night as they navigate the party scene, chasing a sense of belonging and status they’ve always lacked.
At the party, Seth intends to steal more alcohol, while Evan hesitates about staying the course. Evan is mistaken for someone else and ends up locked in a room with a group of guys who snort cocaine and force him to sing a song, while the host of the party expels the motorist and a fight breaks out. Despite the danger, Evan decides to leave the chaos behind, while Seth dives into dancing with a woman who has had too much to drink, only to be confronted by the host for dancing with his fiancée, sparking a brawl. The police are called, and the two friends reconnect outside, attempting to slip away from the escalating mess.
The two friends recount their misadventures and Seth chastises Evan for pulling away from him at a moment when they should be sticking together, while Evan accuses Seth of being held back by their shared history. A reckless shove leads to Seth being struck by a police cruiser driven by a distracted officer, a moment the three of them briefly fear could ruin everything. Fogell, crashing into the chaos from the car, becomes the unwitting focal point of their flight, and the trio darts away to reach Jules’s house party.
At the house, Fogell’s presence underscores his own social ascent: he delivers the alcohol with a swagger and basks in renewed popularity, while Becca’s attempt to woo Evan devolves into a messy, drunken ordeal that ends with her vomiting and telling him to leave. Fogell’s night takes another twist when he impresses a classmate, Nicola, and escorts her upstairs for sex, complicating Seth’s already fragile mood. Seth, increasingly intoxicated, attempts to kiss Jules but is rebuffed, which only worsens his obvious irritation and leads to a drunken misstep that ends with him accidentally headbutting Jules, earning her a black eye.
The authorities crash the party, and Seth awakens to find himself and Evan hurriedly pulling away with Fogell in tow. Slater and Michaels—two officers who had previously joined in on the night’s antics—expose the truth: Fogell had been underage, and they played along to show him that cops can have fun too. To “make it up” to Fogell, they stage a fake perp-wwalk with him in front of their classmates and together destroy the damaged police cruiser, turning a dangerous night into a bizarre, almost comic end to the evening.
Back at Evan’s place, Seth confesses a secret he’d kept for weeks: Evan and Fogell had planned to live together at college, a pact that threatens to wedge Seth out of their circle. Evan admits he’s afraid of living with strangers and that the arrangement isn’t easy for him to face, but he also acknowledges his love for his friends and that he doesn’t want to be pulled apart by fear or selfishness. The two reconcile, promising to navigate the uncertain path ahead together.
The following day, the trio heads to the mall and runs into Jules and Becca. Becca and Seth offer apologies for their drunken antics, and the group wraps the night with a sense of resolution: the boys pair off with the girls, ready to face the next chapters of their lives with a renewed, if imperfect, sense of friendship and belonging.
