High school is hard, especially when you're a freshman in a new town, surrounded by people you don't understand and who don't understand you. Sam was overwhelmed just trying to in. Then the letters started.
Some thought it was romantic to have an unknown admirer, Sam saw things differently. When she responds with her own letter telling him to back off things get even worse.
Twisted admiration is stalking her around every corner in her new high school from Hell.