
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.

While investigating the death of an intruder at Quantico, Jimmy and Kasie are exposed to a deadly biotoxin; the NCIS team calls on Dr. Carol Wilson for help as they race to find the antidote; Torres tries to distract Jimmy's daughter.

The investigation into a car accident that killed a Marine and a young woman brings up upsetting childhood memories for Abby; Ducky says the crash may not have been an accident.

As NCIS investigates the cause of death of a reservist Navy SEAL surgeon, they're forced to bring Vance's daughter to help with a highly dangerous mission.

The NCIS team finds an infamous hacker who could lead them to the world's most wanted cyberterrorist.