Cory and Shawn break into school one night to turn in a late paper. When their flashlight runs out of batteries they search around the chemistry lab for matches. While striking a match, Cory accidentally catches the whole book on fire. This burns his hand causing him to fling the burning wad into the trash can. The boys quickly run out of the school, but Cory, suddenly aware of the inherent danger of a fire in the chemistry lab, runs back and pulls the fire alarm.
The next day he is greeted with applause from students and teachers. Apparently, Janitor Bud was asleep when Cory pulled the fire alarm. He saw Cory running away and told everyone that Cory had saved his life. Cory is now a hero and the whole school is starting to notice him. He gets an A on his charred, unreadable chemistry report, he's chosen to give an inspirational speech at the pep rally and janitor Bud installs a locker genie.
Everything is going well for Cory until Mr. Williams informs him that Philadelphia Tonight wants to do a special report on him at the Matthews' residence. When the news crew arrives, Cory begins to have second thoughts. Plagued by guilt, he talks to Mr. Feeny, who tells him that a real hero is someone who does the right thing, even when it isn't easy. Cory decides to come clean with his parents but he doesn't get off that easy. Mr. Feeny informs him that he has to spend the weekend painting the damaged chem lab.