The year is 1918, and young Ada Cutler is confronted with two frightening situations: the brutality of war and the terrifying nature of an influenza pandemic. After nursing her aunt and uncle back to health from the illness, it becomes apparent that Ada is immune to the virus. The family doctor suggests that Ada help nurse soldiers who have fallen ill with influenza back to health at a nearby army base. While carrying out her duties, Ada utilizes her observation and detective skills to uncover a grim secret.