Bob Lee Swagger and wife Julie join his former Marine unit in Germany and narrowly escape a deadly terrorist attack. FBI Agent Nadine Memphis, meanwhile, takes a job in Washington with Patricia Gregson.

Bob Lee investigates the terrorist attack that may have targeted his Marine unit. Memphis helps on the ground in Germany. Flashbacks to Afghanistan help shed light on who might be after them.

Bob Lee finds Isaac Johnson in Texas after an attempt on his life. Nadine discovers just how much influence Patricia Gregson wields, and a traumatized Julie fights to stay strong for her family.

Bob Lee and Isaac learn the world's greatest assassin is in the U.S. Flashbacks to a mission in Afghanistan reveal his identity: Solotov. Nadine comes to Texas with suspicions of a conspiracy.

Bob Lee works to piece together Solotov's motive for targeting their unit. Nadine uncovers a surprise witness to the event that set everything off. Solotov's hunt has him hiding in plain sight.

Bob Lee tracks Solotov's money, pitting himself against a Mexican cartel. Nadine helps a journalist investigate a cover-up involving Bob Lee's unit. Julie makes her frustration heard with a gun.

Bob Lee and Isaac must team up to escape a Mexican prison before Solotov finds them. As Nadine digs deeper into Atlas, the cover-up points back to Bob Lee's unit. Julie has problems with the law.

Bob Lee tries to draw out Solotov, but realizes he holds the upper hand; flashbacks reveal the origin of Solotov; Isaac is courted by his creator. Season Finale.

Retired Marine sniper Bob Lee Swagger is recruited by his former commander to stop an assassination of the president; and FBI agent Nadine Memphis investigates potential assassins.

Bob Lee tries to protect his family while incarcerated; and Isaac aims to silence him. In other events, Nadine contacts Bob Lee's wife, Julie, who's dealing with the backlash against her family.

Bob Lee reaches out to Nadine while evading his pursuers; and Isaac juggles his double life while trying to find Bob Lee.

Bob Lee plans his next moves; and Isaac ties up loose ends. In other events, Nadine investigates the Ukrainian connection.

Bob Lee locates the bullet from the assassination, which leads him to a radical militia group and Isaac; and Nadine is locked in a deadly game of cat and mouse with Payne.

Bob Lee tracks down his former instructor, who he hopes will help him find the shooter; Nadine interrogates Payne; Isaac realizes that he's in over his head; and a reporter makes Julie an offer.

Bob Lee travels across the country in order to find the shooter; Julie deals with a family betrayal; Nadine contacts a Ukrainian reporter who can explain the conspiracy; and Isaac questions his allegiance.

Bob Lee and Nadine plot to secure evidence that could expose the conspiracy. Isaac searches for an exit strategy. Payne tries to flee. Julie and Mary are in danger.

Bob Lee negotiates an exchange in order to save his family; Nadine juggles her allegiances to Bob Lee and the FBI; and Isaac strikes a deal for his freedom.

Bob Lee, Julie, Nadine and Isaac work together to breach the Russian embassy, save Mary, shut down the conspiracy and prove Bob Lee innocent.