Kara Green (Marissa Neitling) is very close to flushing out the mole inside the White House in the upcoming episode of "The Last Ship," but her discovery may come far too late.

In the episode titled "Scuttle," the promo reveals that the White House has been compromised and that Captain Tom Chandler (Eric Dane) and his squad are in danger of being sent to jail. In the clip, an officer tells the captain that he is putting him and the others under arrest. Chandler quickly realizes that something has gone terribly wrong at St. Louis. Although President Jeffrey Michener's (Mark Moses) replacement is doing his best to keep America afloat, he does not know that there are wolves in sheep's clothing in his team.

Allison Shaw (Elisabeth Röhm) has the full backing of the regional leaders in preventing the United States from centralizing its powers. Kara tells whoever she is talking to on the phone that the White House has a mole, but she does not know yet who it is. She must be careful though since Allison is aware that the Navy lieutenant has been snooping around. The new Chief of Staff can order Kara's assassination with a snap of her fingers. She has already ordered the death of many in the course of her mission. Another life will not make any difference.

The unrest in the White House is now taking center stage in the storyline of the TNT series. After focusing on saving Mike Slattery (Adam Baldwin) and the others from the pirates in Asia, the action is shifting to St. Louis, where a very unstable American government is on the verge of a coup d'état.

Executive producers Hank Steinberg told Buddy TV in June that one of the highlights of season 3 is the political turbulence set to take place.

"In Season 3, the storyline is split between the action in Asia and the Presidency in the new White House in St. Louis. ... The drama is between geo-political issues of how to hold the country together and the question of how many resources should we give to saving the rest of the world when America is stretched very thin and trying to repair itself," the EP said.

"The Last Ship" season 3 airs Sundays at 9 p.m. EST on TNT.