The exploits of the Los Angeles–based Office of Special Projects (OSP), an elite division of the Naval Criminal Investigative Service that specializes in undercover assignments.
Callen and Sam work with Navy Capt. Harmon Rabb, Jr. to apprehend spies aboard the USS Allegiance. Also, Hetty partners with Marine Lt. Col. Sarah “Mac” Mackenzie to neutralize a missile attack in the Middle East, and Kensi and Deeks are trapped in a mobile CIA unit in Iraq while under attack by ISIS.
Faced with multiple cases worldwide, the NCIS team splits up, with Callen and Sam working with Mossad Agent Eliana Sapir in Tel Aviv, and Kensi partnering with DOJ Agent Lance Hamilton in Los Angeles.
Callen and Sam run protection detail for retired Navy Admiral Kilbride in an operation to locate a missing Naval intelligence officer.