"Aliyah" is the twenty-fifth and final episode of the sixth season of the American police procedural drama NCIS, and the 138th episode overall. It originally aired on CBS in the United States on May 19, 2009. The episode is written by David North, directed by Dennis Smith, and was seen live by 16.51 million viewers.
"Aliyah" picks up following a cliff-hanger in the previous episode, "Semper Fidelis", in which Tony DiNozzo fatally shoots Ziva David's Mossad boyfriend, Michael Rivkin, in self-defense. It also follows the "Legend" storyline, culminating in Ziva's departure from NCIS and eventual captivity in Somalia.
Etymology
"Aliyah" is a Hebrew word which literally means "going up" or "ascent". It is most commonly associated with Jewish immigration to Israel and return to the Holy Land. In this case, it is a reference to Ziva's return to Israel and her blood family.
Plot
Despite Ziva's efforts to help him, Mossad Officer Michael Rivkin (Merik Tadros) dies in the hospital, having suffered injuries from his fight against Tony in the last few seconds of the previous episode ("Semper Fidelis"), while Tony survives albeit with a broken left arm. While Tony claims to have acted solely in self-defense, Ziva, infuriated, does not believe him and Director Leon Vance is doubtful that he could have fairly survived the brawl with a Mossad assassin who was also a member of the Kidon Unit. Matters are further complicated after Ziva's apartment is destroyed in an explosion, severely damaging the evidence and the crime scene. Gibbs approaches Ziva, knowing that the gas lines were cut and the explosion was intentional, and asks her if she knows any possible suspects. She deflects, even when Gibbs notes her stoical response, reminding her that it is her home in question.
Ducky confirms that Rivkin and Tony's injuries line up with the latter's version of the story and provides a reason for his ability to win the fight: Rivkin was intoxicated by alcohol. As tension mounts, Vance has Gibbs, Tony and Ziva accompany him on the next flight to Tel Aviv, Israel, having been summoned there at the request of Eli David (Michael Nouri), the enigmatic and powerful head of Mossad and also Ziva's father, while McGee and Abby stay in Washington D.C. to work on the case.
In Israel, Eli interrogates Tony, accusing him of killing Rivkin solely out of jealously; DiNozzo in turn accuses Eli of sending rogue agents to Washington and ordering Rivkin to become involved romantically with Ziva to keep an eye on her. Tony later approaches Ziva, who viewed the interrogation, and tells her that Rivkin was "playing" her under orders from her father. She refuses to believe him, and he maintains that he had no choice in killing Rivkin. After he urges her to "take a punch" and "get it out of [her] system", Ziva snaps, knocking him to the ground while furiously contending that he could have chosen to wound, rather than kill, during the brawl. When he quietly asks her if she had loved Rivkin, she answers that she may never know. Afterwards, Ziva confronts Eli in his office, demanding to know if her relationship with Rivkin was real. He admits that he does not know, confirming Tony's assertions. He further states that he is no longer certain of her loyalty, insisting that she return to Mossad as a full-time operative and complete Rivkin's assignment.
In Washington, McGee and Abby manage to recover various emails and pieces of information from Ziva's laptop that allow them to assemble basic conclusions about the objective of Rivkin's mission and they also discover that Rivkin was in contact with Ziva. Gibbs, having gotten the information, ultimately decides to leave Ziva in Tel Aviv, hoping to give her time to "remember who she can trust" and consider returning to NCIS. The team is shocked by the turn of events, and Ducky notes that Gibbs took to Ziva more quickly than to any other agent before her and treated her as family. However, Vance confronts him shortly afterwards and questions the integrity of Ziva's position at NCIS as well as her motives for killing her half-brother, Ari Haswari, four years earlier to save Gibbs. Though Vance suggests that Ziva may serve them well at Mossad, Gibbs counters back, stating that if Vance knows Eli, then they may never see Ziva again.
Ziva is later shown having once again been recruited into Mossad and embarking on a mission to stop a terrorist cell. The episode ends on a cliffhanger when in the Cape of Africa, terrorist leader Saleem Ulman (Omid Abtahi) enters a room and asks a tortured Ziva for information on NCIS.