
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.

NCIS is called in when Navy Chief Warrant Officer Rafi Nazar is suspected of trying to sell stolen classified Navy software used to pilot combat drones.

The lead suspect in a murder investigation is a woman that Gibbs' friend met on a dating site; Sloane has a secret admirer on Valentine's Day.

After a civilian research vessel in the North Atlantic picks up a small boat of wounded Navy officers, NCIS arrives on the ship and is forced to hide after discovering terrorists are onboard.

The team tries to piece together how a retired Navy officer obtained a rare and valuable coin.