At the center of the plot of this TV series is a professional sniper named Bob Lee Swagger who had been serving at the American army for many years. But after the death of Bobbys friend and sidekick during a secret operation he once and for all decided to stop with service and now he lives a quiet life. But one day the past reminds about itself. The retired soldier is asked for help to the secret service. They tell him an attack to the head of the state is getting prepared. And he is one of the few who can help.