[s17e10] The North Pole -

: Mark Harmon, Cote de Pablo, Emily Wickersham, Wilmer Valderrama, and Jack Fisher as Phineas.

: The mission results in the death of Ziva's longtime friend and contact, Adam Eshel , who is found badly beaten and eventually dies from his injuries. Before passing, Adam provides a cryptic clue that leads Gibbs to the truth about Sarah's identity. Character Relevations & Arcs [S17E10] The North Pole

: Bishop (Emily Wickersham) is tested by Odette , Ziva's landlady and former CIA contact. After Bishop refuses to compromise her ethics for a mysterious drive, Odette reveals it was a test and offers her "specialized training," hinting at Bishop's future shift into a more covert role. : Mark Harmon, Cote de Pablo, Emily Wickersham,

: It is confirmed that Tony DiNozzo has known Ziva was alive for some time, having tracked her down in Cairo shortly after his departure from the team. Character Relevations & Arcs : Bishop (Emily Wickersham)

The core conflict revolves around Ziva's attempt to neutralize the terrorist threat posed by . While the team previously believed Sahar had been eliminated, "The North Pole" reveals that the woman killed earlier in the season was merely a decoy.

The episode provides critical answers to long-standing fan questions while setting up future storylines: