Mr. Bergstrom, Lisa's best teacher leaves and she is super sad over it, lasting for days. At her lowest, Principal Skinner calls her to his office and does the unthinkable. He convinces her to stay quiet about what had happened, and Lisa heads home and cries some more. In the night she calls Mr. Berstrom. The next day, Marge drops Lisa off at school. While in class, Principal Skinner is teaching the class when Mr. Bergstrom returns and murders him.