At Sloppy Secondary High School, a new teacher, Ms. Vickers, has organized a charity event called a 24 Hour Famine, the first of its kind in five years after a troubling incident during the last famine. Ten students sign up for extra credit: Cathy, Sarah, Darren, Nick, Terry, Vanessa, Andrea, Katie, Jenny, and Peterson. Before the timer starts, Vickers asks Jenny to recount what happened at the previous famine, and Jenny shares a chilling rumor: the organizer, Philip Balszack [Nathan Durec], was somehow disfigured by acid when he attempted something inappropriate with Cathy in the chemistry lab. Balszack disappeared afterward, and Cathy was briefly institutionalized. The tone of the day shifts from hopeful charity to a growing sense of danger as the past bleeds into the present.
Before the famine begins, Katie hides food in a gym washroom, and is confronted by the masked killer—the Nailer [Ryan Nicholson], a carpenter in disguise who hurls a knife into Katie’s forehead and disappears with her body. As the famine proceeds, the Nailer methodically targets stragglers: Terry has his throat slit while sabotaging food in the cafeteria, Peterson is impaled through the head during a bizarre moment with a Swiss Roll, and Vanessa is toppled onto a spike that erupts from Peterson’s head. The gym and hallways become a maze of fear as the students realize the threat is not a rumor but a brutal, literal killer on the loose.
Jenny uncovers a grimmer layer of the mystery when she discovers the Nazi-principal dead, his eyes removed while he watched explicit material, and she is kicked out amid disbelief from the staff. She re-enters the building using keys stolen from two teachers murdered in the parking lot and finds Darren’s fried, severed head in the cafeteria freezer. Reunited with Vickers and the remaining students in the gym, Jenny faces a voice over the PA that grows increasingly menacing, and the group hides as the truth about the day’s danger deepens. In the aftermath, Tim—the scarred janitor and prime suspect—turns up dead in an office.
As the tension escalates, Vickers returns to retrieve Cathy, and the others attempt a breakout. Cathy, now violent and unhinged, reappears with a claim that she stabbed Vickers in the gym during the struggle. Jenny and Nick push toward the gym, but Nick is gruesomely disemboweled by Vickers, and Cathy scalps Andrea in a brutal moment of vengeance. Vickers and Cathy pursue Sarah, cornering her in a classroom, where they mutilate one breast and stab her. The chaos peaks as Jenny confronts Vickers and Cathy with a nail gun, the latter revealing her role in the previous events and her connection to Balszack’s past.
In a shocking reveal, Vickers discloses she is Balszack, having survived a series of surgeries and a gender transition, returning for revenge. Cathy explains the rumors that surrounded Balszack and Cathy years earlier: their supposed “friends” dared Cathy to seduce him, and when she tried, he rejected her, an act that ended in tragedy. The truth unravels the motive behind the current slaughter, tying together the patterns of the last famine with the present carnage. The confrontation reaches its climax as Jenny fires a final, reckless shot from the nail gun, grazing Vickers and striking Cathy in the head. Cathy collapses, followed by Vickers who falls onto Cathy's knife, sealing their fates.
In the end, Jenny escapes the chaos wielding the nail gun and wearing The Nailer’s head, a grim trophy that underscores the night’s brutal transformations. The campus returns to silence, but the memory of the 24 Hour Famine lingers as a cautionary tale about rumor, revenge, and the cost of desperate choices.
