When a plot to assassinate the President of the United States is discovered, Marine Sniper Bob Lee Swagger is recruited by his former Commander, Isaac Johnson, to help prevent the assassination attempt. Meanwhile, disgraced FBI agent, Nadine Memphis, takes on the investigatory grunt-work prior to the President’s visit.

Bob Lee struggles to protect his family from inside the walls of a detention center while Isaac tries to figure out how to silence him.

Bob Lee reaches out to Nadine as he evades his pursuers. Isaac juggles his double life as he tries to find Bob Lee.

In a flashback to their time serving in Afghanistan, Bob Lee and Isaac clash with opposing ideologies. Nadine investigates the Ukrainian connection.

Bob Lee finds the bullet from the assassination, leading him to a radical militia group. Nadine is locked in a deadly game of cat and mouse with Payne.

Bob Lee tracks down his former instructor Rathford O’Brien to help him find the shooter. Nadine interrogates Payne. Isaac discovers he's in over his head.