New York has been plagued by a series of mysterious suicides. One morning, four girls from the same high school awaken feeling exhausted and disoriented, unable to recall the events of the previous night. At school they learn that one of their classmates has taken his own life, and the day is cancelled. Rather than heading home, the girls are lured into a nearby park by butterflies visible only to them. There, a man and a woman confront them and reveal that they all died the night before.