In Colombia, the notorious Luis Cali orchestrates a brutal takeover of the Palace of Justice, demanding his father's release, Enrique Cali. When authorities inform him that his father has been extradited to the United States, Luis and his men commit several murders before escaping via helicopter to pursue their agenda in the U.S.
Meanwhile, at The Regis High School, a prestigious prep school for boys, we find Billy and his mischievous friends: Joey, Snuffy, Ricky, and Hank, who specialize in pranks. One of their favorites? Changing their school's sign from "Regis" to "Rejects." Many of them are misfits, expelled from previous institutions, and despite his checkered past, Billy has been given another chance by Dean Parker, who is determined to ensure Billy graduates, even if it means putting him on menial kitchen duties for various offenses.
One night, Billy and the gang discover a hidden entrance in the kitchen that leads to a basement chamber. There, they indulge in some colored vodka sneaked inside mouthwash bottles and make an improvised phone call to a sex worker, sparking unforeseen consequences when Dean Parker overhears them. Things take a serious turn when Donoghue, one of their group, is removed from campus due to the need for his family's protection—the judge presiding over Enrique's trial.
As Luis and his gang of criminals cross the border, they soon infiltrate The Regis School, slaughtering a security guard and a faculty member in their quest for revenge. Upon discovering Donoghue's absence, Luis shifts his focus, finding out that Billy and his friends are the offspring of influential men, giving him leverage over their families as he sets a deadly plan in motion. He wires explosives throughout the school, with one detonator strapped to his wrist, while his associates hold firm guard outside with firearms.
The situation escalates, prompting a response from the sheriff, whose car is obliterated—a clear indication that reinforcements are desperately needed. The FBI steps in with Deputy Director Brown leading the charge, denouncing any negotiations with terrorists under General Kramer's military authority. Dean Parker, away from the chaos, offers guidance on managing the unfolding crisis.
Luis allows some faculty members to escape but keeps 92 individuals hostage in the dining room, enforcing a draconian rule: all must return at each hour's bell or face dire consequences. With little time to waste, Billy and his friends quickly devise a plan to gather critical intelligence to relay to the FBI and soldiers. They share tight quarters with several other boys, including the ingenious Yogurt, who devises a means to disarm the detonator using a model spaceship.
Eventually, amidst a litany of distractions, Billy finds an unnoticed escape route through the storm drains. He rushes to the outside team organizing a rescue mission but is warned that returning might jeopardize their plan. Following his instinct to intervene, he makes it back to the school just in time—drenched and barely escaping detection by claiming a shower had prevented him from hearing the bell.
As the stakes continue to soar, Joey, the son of mob boss Albert Trotta, seizes a firearm in a panic but tragically falls victim to the chaos. With negotiations failing and the imminent threat of violence hanging in the air, the required course of action becomes glaringly clear: sacrifice must be made to ensure the safety of those held captive. As the expected release of Luis's father approaches, a riot disrupts everything, resulting in Enrique's demise.
In a race against the clock, Billy and Yogurt concoct a bold strategy to disable the detonator housed in the office, utilizing the vents to sneak in. The task proves complicated when one of Luis's men unexpectedly intrudes on their escape route. However, Dean Parker firmly believes in Billy's resourcefulness, entrusting him to lead the other students to a fortified hideout—built in 1881 and expected to withstand any blows.
When the army moves in, chaos reigns as those attempting to fire upon the terrorists are eliminated one by one. Billy manages to guide the others to safety but inadvertently finds himself captured. As the drama unfolds, Luis attempts to trigger the detonator, but when Yogurt’s model spaceship distracts him, there's a moment of hope. Just as danger culminates, Dean Parker arrives in the nick of time to rescue Billy.
Despite the harrowing ordeal and his bravery, Billy learns from Dean Parker that he will face punishment for his past actions. But at the end of this tumultuous saga, the boys emerge triumphant, celebrating their survival—though one member remains conspicuously absent until they are finally reunited with Billy.
