
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.

Agent Knight's past resurfaces when her ex-boyfriend, a National Parks Service agent, teams up with NCIS to investigate a campsite murder.

Agent Parker steps up to protect director Vance after a terrifying home invasion; the team detects advancements in Jessica and Jimmy's blossoming romance.

The team turns to Holly Snow for help when a Navy officer's death is connected to a prostitute.

Gibbs, Fornell and the team try to determine the truth when a polygraph specialist's night job leads to murder.