Typhoon, a mutiny and a Washington coup d'etat will force Marcus and his crew into unlikely alliances. As Sam's grief strains his loyalty to Marcus, will Sainte Marina get the supplies it so desperately needs? How far will Marcus go to ensure the crew's survival -- will it cost him his life?

In the exciting season finale, a violent battle for control erupts on the submarine, which leaves the Colorado vulnerable to capture by a third party -- one with an exploitative plan. Can Marcus and Sam take control of the sub before it's too late?