Jack Swyteck is at his office when he receives the emergency text from Riverside Day School. Both his daughter, Righley, and his wife, FBI agent Andie Henning, are in danger. Andie is in the school's rec center when she hears the fire alarms, then loud popping noises and screams coming from the hallway. A trained law-enforcement officer, Andie knows she's supposed to stay locked down inside the room. But Righley is in her kindergarten classroom and Andie must get her to safety.