NCIS has been no stranger to significant cast turnover in its long history, with many viewers previously left wondering if the show could sustain itself. Arguably, the most shocking shake-up to the cast came when Cote de Pablo's Ziva left NCIS. From her first appearance, Ziva was a big part of the franchise.

It hit the NCIS fan community hard when CBS announced that Ziva would be leaving the highly successful series. Details on why the character was written out were never fully confirmed, but quotes from de Pablo and lack of confirmation from production have led to conflicting rumors.

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Who Was Special Agent Ziva David on NCIS?

NCIS' Tony DiNozzo and Ziva David in the NCIS office, looking off camera

The first appearance of Ziva David was in the Season 3 premiere as an agent of the Israeli Mossad. She was introduced in a tumultuous time on the show because Kate had just been killed by Rudolf Martin's Ari Haswari in the Season 2 finale. Things were slightly awkward because, as it turned out, Ziva was Ari's half-sister. But it didn't take long for Ziva to declare her allegiance, shooting Ari to save Gibbs.

After that, Ziva became a liaison officer between her father, the director of Mossad, and NCIS's Director Jenny Shepard, serving in that role for four years, which amounted to three seasons. She then returned to Mossad but was captured in Somalia while on assignment before Gibbs, Tony and McGee rescued her. Following that, she resigned from Mossad and became a probationary NCIS agent and a US citizen.

Ziva's time at NCIS came to an end in Season 11. She, Tony and McGee resigned from NCIS to protect Gibbs from a political vendetta, but Ziva chose not to rejoin the agency when the issue was resolved. Instead, she returned to Israel and was supposedly killed offscreen in Season 13 during an attack on her father, Eli David's, farmhouse. Viewers later learned that she and Tony had a daughter named Tali. After finding out the news, Tony also chose to leave NCIS.

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Why Did Ziva Leave NCIS?

Cote de Pablo as Ziva David in NCIS

In a 2013 interview with TV Guide, Cote de Pablo indicated that she left NCIS because of a personal issue: "As far as my decision to leave, that's a personal thing, and I'd rather leave it at that." However, in a 2016 Q&A about her departure, she told a different story, which involved how her character would be treated in the future. She noted, "They were going to send [Ziva] back to Israel and assemble her an unfortunate, miserable woman. I said, 'What do I leave all the women that are watching and following the show?' And I didn't think it was fair. So, I said, 'Unless someone can really write something fantastic for [Ziva], I won't go back.'"

Even with all of that, there's no complete answer, although some cast members, including David McCallum, were markedly disappointed by her sudden choice to leave. Regardless, fans were unhappy with how Ziva was written off and clamored for a cameo appearance for years. Then, in Season 17, it finally happened. Ziva comes back to NCIS for four episodes. During that stretch, the writing revealed that Ziva had survived the bombing attempt and had gone deep undercover to find the perpetrators. With the help of Gibbs, Ziva accomplished her goal, killed the woman who had been hunting her and finally reunited with Tony and Tali offscreen, thus, giving Ziva's character a more fitting send-off.