
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.

A girl's kidnapping turns into something bigger when her grandfather complicates the investigation.

Gibbs and Fornell attempt to track down the leader of a drug ring who supplied drugs to Fornell's daughter; the team deals with the case of a missing cadaver from the NCIS autopsy room.

Flashbacks reveal the murder case that first introduced young Gibbs to NCIS and to Ducky.

The discovery of two dead bodies in a forest leads the NCIS team into the wild world of modern-day treasure hunting; Gibbs and Fornell get deeper into their search for the opioid kingpin.