Silver War

A deceased Marine is found encased in a Civil-War era tomb at the Smithsonian museum and evidence later comes to light suggesting that he was probably buried alive. In the meantime, Ziva David returns to NCIS, having been assigned to Gibbs's team as a liaison officer for Mossad by the new director of NCIS, Jenny Shepard. Gibbs is angry she did so without consulting him, but Jenny insists that the team needs Ziva. She is forced to prove her worth to the team as they track down the people responsible for the Staff Sergeant's death, which is linked to a Civil War treasure and a lone rogue group who are working behind the scenes. When Ducky and Ziva are placed in a difficult position, Ziva shows her value by saving both their lives and as such, is finally accepted into the team, officially replacing Kate Todd.