Leon Vance's Entire NCIS Backstory Explained

"NCIS" focuses primarily on the field team of the Naval Criminal Investigative Service led by Agent Leroy Gibbs (Mark Harmon), but the stoic mentor and his team of highly-qualified agents aren't the only characters on the show. The supporting cast provides ample drama and intrigue, perhaps none more than the Gibbs' boss, Director Leon Vance (Rocky Carroll). First appearing in the Season 5 episode "Internal Affairs," Vance was introduced as the assistant director of the NCIS under the previous director Jenny Shepard (Lauren Holly). In the wake of Shepard's death, Vance was promoted to her position, where (after some initial friction) he becomes a stern but even-handed boss who genuinely has the best interests of his agents in mind.

That being said, the NCIS director does have a decidedly murky past, with very little that can actually be said with certainty about his background. Let's dig into the history of Director Leon Vance of the NCIS and see just what we can learn about the team's mysterious boss.

Vance grew up in Chicago, where he trained to be a boxer (detailed in the Season 6 episode "Knockout"). He later attended the U.S. Naval Academy, where he was commissioned with the rank of Second Lieutenant. In 1991 Vance was a student at the Naval War College, where he became fascinated with black operations. Approached by the NIS (the precursor to the modern NCIS), Vance was recruited by Special Agent Whitney Sharp (in a flashback from the Season 8 episode "Enemies Domestic").

Trained by Sharp, Vance joined a clandestine NIS mission codenamed Operation: Trident and tracked down a mysterious agent known only as The Russian. Vance had his first encounter with Eli David (Michael Nouri) on the mission, who warned him that the Russian was aware of the operation and intended to kill Vance. Eli then betrayed Vance to the Russian, but this turned out to be a ruse to lure the villain out so Eli could kill him. The Russian escaped, but Eli and Vance took out his hit squad, and Vance soon found himself rising through the ranks of the NCIS for his handling of the situation.

Vance took over as director during Jenny Shepard's leave of absence between the Season 5 episodes "Internal Affairs" and "Judgment Day, Part 1." Shepard is killed during the events of the two-part "NCIS" Season 5 finale, and Vance soon ascends to the rank of director. His first act is to scatter Gibbs' team to various other assignments and provide him with a new group of investigators under his command. This initially creates tension between Vance and Gibbs, but it's soon revealed that this was part of a greater plan to flush out a mole within the NCIS. Vance and Gibbs would continue to butt heads due to the latter believing his new boss was too close to Mossad. Vance also thought that Ziva (Cote de Pablo) was a Mossand plant, but eventually, he and Gibbs came to develop a mutual understanding and respect for each other, particularly after the NCIS team rescues Ziva in the Season 7 episode "Truth Or Consequences."  

There's still a great deal about Director Leon Vance that we don't know, but we can say that he is a dedicated agent of the NCIS and a stern but fair commander. His past hasn't been fully revealed to us, but half the fun of a series like "NCIS" is peeling back the layers of a mysterious character and learning more about what makes them tick.