
Naval Criminal Investigative Service Special Agent Leroy Jethro Gibbs leads a group of colorful personalities in investigating crimes -- ranging from murder and espionage to terrorism -- that have evidence connected to Navy and Marine Corps personnel. The team includes MIT graduate Timothy McGee, Ellie Bishop, who specializes in international threat assessment, charismatic and unpredictable Nick Torres, and forensic psychologist Jack Sloane. Dr. Donald "Ducky" Mallard brings his vast experience in forensics into play to help solve cases.

When Abby is asked to take over for a government scientist who has gone missing, the team fears that she will meet the same fate as her predecessor.

Gibbs and the team must work with ICE and FBI agents when a security breach results in the death of an ICE agent; Tony comes face to face with Michael Rivkin (Merik Tadros).

Ziva has a tense reunion with her father, the head of Mossad; Gibbs is forced to make a shocking decision.

Two mercenaries are found dead on Gibbs' boat; Gibbs must consider his former mentor in a new light.