Boston Public (2000) : 1x9

The first day back at school has barely begun when the police show up looking for a murder suspect. A botched robbery has gone down a few blocks away and the panicked assailant, wearing a Winslow High letterman's jacket, shot and killed a man before heading towards school grounds. The police think the suspect is a student who is hiding on campus and demand to begin the search at once. Meanwhile, oblivious to the tense situation, Lisa and Buttle decide to have sex in the deserted boiler room. Unfortunately, Riley and an officer stumble upon the couple during the investigation and catch them in the act. Riley agrees to keep quiet about the affair for now, but urges Buttle to break it off before he loses his job…or worse. As the hunt continues, it becomes a code red condition, locking both teachers and students in their classrooms. Eventually, Lauren realizes that a pupil in her class might be the suspect but before she can take action, the desperate student whips out his gun and takes La