Spremljamo zgodbo žene in matere Diane, ki na videz živi popolno življenje z možem profesorjem in hčerko Emmo. Toda ob 15. obletnici tragičnega dogodka, ki se je zgodil na njeni bivši srednji šoli, postane jasno, da so imeli travmatični dogodki močan vpliv na njeno življenje. Diana in njeni sošolci so bili takrat priča streljanju, v katerem je umrlo več dijakov. Med žrtvami je bila tudi njena prijateljica Maureen.
A dramatic thriller about Diana, a suburban wife and mother who begins to question her seemingly perfect life--and perhaps her sanity--on the 15th anniversary of a tragic high school shooting. In flashbacks, Diana is a vibrant high schooler who, with her shy best friend Maureen, plot typical teenage strategies--cutting class,fantasizing about boys--and vow to leave their sleepy suburb at the first opportunity. The older Diana, however, is haunted by the increasingly strained relationship she had with Maureen as day of the school shooting approached. These memories disrupt the idyllic life she's now leading with her professor husband Paul and their young daughter Emma. As older Diana's life begins to unravel and younger Diana gets closer and closer to the fatal day, a deeper mystery slowly unravels.