One night while drinking with friends, Willoughby High School teacher Rick Latimer sees his ex-wife, Kimberly, on a date with the lawyer who handled their divorce. Drunk, Rick becomes jealous, grabs a baseball bat from behind the bar, hits the lawyer with the bat, then smashes all the windows in the lawyer’s sports car. Police arrest Rick, while Kimberly reiterates that she divorced him because he refused to grow up, as this incident has just proved. Rather than suspend or fire Rick for his behavior, the school board assigns him to be the new principal at Brandel High School, an aging, inner city school that is falling apart and covered in graffiti. The student body consists largely of delinquents expelled from other schools who do not care about learning. Brandel High is controlled by two rival gangs, one headed by a white student named “White Zac,” the other by a black student named Victor Duncan. Believing he can clean up the school and clean up his image at the same time, Rick Latimer calls a school assembly and announces “no more.” No more skipping class, no more gambling, extortion, selling drugs on campus, gang intimidation, arson, robbery, or rape. As Rick gives his speech, Victor Duncan walks into the auditorium and mocks him in front of the entire student body, then announces that it is his school and he makes the rules, causing a small riot to erupt. Despite his poor start, Rick carries through with his plan and assigns teachers to act as security guards. Rick catches drug dealers selling drugs in the bathroom and flushes the drugs away. When he catches students hanging out in the halls during class time, he sends them to class. History teacher Hillary Orozco and other teachers protest Rick’s actions, saying they are making progress with the students who want to be in class. However, the students Rick is forcing out of the halls and into class are disrupting things. It is “tradition” to let students who do not want to learn to linger in halls, so the others can get on with their studies. Rick argues that every student deserves an education and they cannot let the problem students slide because it is the easy thing to do. Such attitudes tear at the very foundation of the school. Rick goes to the home of single mother Treena Lester, a student he caught selling drugs. Saying she is a good student and can graduate in three months, Rick offers to tutor her each day before school starts. The next day, Rick is at school at 6 a.m., but Treena does not show up. Instead, members of Victor Duncan’s gang come to the classroom and severely beat Rick. They also disassemble Rick’s motorcycle. A bloody, beaten, and bruised Rick gets the auto mechanics class to rebuild the bike. That afternoon, Rick gets on the motorcycle and breaks up a drug deal being conducted near school. Victor’s men give chase and corner Rick, but do not shoot him as there are too many witnesses. Jake Phillips, the school’s head of security, says he can protect Rick on campus, but not off school grounds, and advises that he be careful of Victor’s gang, noting that Victor is an especially vicious man. Late one day when most people have left the school building, rival gang leader “White Zac” attacks Hillary Orozco in her classroom and attempts to rape her. Hillary throws a chair out a window which gets Rick’s attention. He rides his motorcycle into the school and up the stairs to rescue her. “White Zac” is arrested and Victor Duncan is happy no one is there to contest his reign as leader of the school. While Hillary recovers from her injuries, a substitute teacher refuses to teach such unruly students, so Rick teaches the class. He helps Arturo Diego, who can barely read, and also offers encouraging words to Emile, a member of Victor’s gang. Emile decides to leave the gang, but they retaliate by trying to hang him. Rick finds Emile before he dies and rushes him to the hospital, where he eventually recovers. Rick goes to Hillary’s home to check on her and she invites him to stay for dinner. However, a few days later, Hillary announces she has a job at a boarding school in Connecticut and will not be returning to Brandel High. Rick confronts Victor who promises to kill the principal if he shows up at school the next day. While security chief Jake Phillips advises Rick not to come to school, Rick ignores the warning and shows up. At the end of the day, many students gather outside the school, waiting for a showdown. With the school deserted except for Rick and Jake, Victor and his men go inside. They lock Jake in a storeroom, while Rick hides in the locker room. When Victor finds Rick, he tells his gang member “Jojo” to cut Rick’s face with a knife and kill him. Jojo refuses, saying he will not go to jail for killing someone. Victor holds a gun to Rick’s head, but another student knocks the gun out of his hand. Rick and Victor get into a fist fight and Rick knocks Victor out. Police arrest Victor. Stunned at their leader’s defeat, a student asks Rick who he thinks he is. Rick replies, “I’m the principal, man,” and rides away on his motorcycle.