Kovac and Benton are rushed to the site of a school shooting where they disagree over who is more critical: the injured gunman or one of his victims. Kovac later treats a heavily pregnant teenager who didn't know she was pregnant and refuses a C-section to save the baby's life. After Abby catches Carter injecting a patient's leftover pain medication into his wrist, Kerry, Mark, Benton, Chen and Anspaugh try to convince him to seek professional help.