The aftermath of a high school shooting leaves Deanna Cartwright (Erika Christensen) seriously wounded and nine others dead, including the perpetrator. Det. Martin Van Zandt (Victor Garber) is assigned the unenviable task of investigating the crime and finding someone to hold responsible. His attention settles on Alicia Browning (Busy Philipps), a darkly troubled outsider who, as the only person present throughout the entire incident, is both the key witness and a possible suspect. Further complicating her isolated existence, Alicia's high school principal compels her to pay a reluctant visit on the still-hospitalized Deanna. Privileged and popular, Deanna differs dramatically from the alienated Alicia. Yet, beneath an upbeat appearance, she is struggling desperately with the emotional and physical scars left by the attack. Over the next few days, united by nothing more than their common suffering, the two young women form an unlikely friendship to cope with the tragic events that threaten to overwhelm them