In the fictional town of Briarwood, Ohio, in mid-May, a strange temporary English teacher appears at the local high school — Miss Evelyn Cross. She always wears a white medical mask, speaks softly, and carries herself with an unsettling calm. To the students, she seems like an easy target for mockery — especially for the defiant teenager Jack Miller, notorious for his cruel school pranks.
But one joke goes too far. After Jack’s disappearance, the school and the town try to cover it up, dismissing everything as an unfortunate accident. Only his best friend Noah begins his own investigation and uncovers a forgotten urban legend — about “The Smiling Substitute,” the spirit of a teacher who died violently decades ago after being tormented by her students. Every May, she returns to deliver one final lesson to those who cross the line.
