NCIS

The Naval Criminal Investigative Service commonly referred to as NCIS is responsible for investigating crimes related to the U.S. Marine Corps and the U.S. Navy. Remnant interaction with the agency is usually with the Major Case Response Team in Washington D.C. However, an operation led by General David Gonzalez was ran with the NCIS Office of Special Projects in Los Angeles.

In 2019, it is revealed that both the agency's Director Leon Vance and Washington D.C. MCRT SAIC Leroy Jethro Gibbs objected to Andros Khayman bringing the Astro Megaship to the Washington D.C. Navy Yard for a number of different reasons following the death of his brother Bryan in 2010.

Los Angeles OSP

 * Kensi Blye (Field Agent)
 * Grisha “G” Callen (Special Agent In Charge)
 * Marty Deeks (Field Agent)
 * Sam Hanna (Field Agent)
 * Retired USN Adm. Hollace Kilbride (Director of Special Operations)
 * Fatima Namaz (Field Agent)
 * Louis Ochoa (Deputy Director)
 * Devin Roundtree (Field Agent)

Washington D.C. MCRT

 * Kasie Hines (Forensic Specialist)
 * Andros Khayman (Special Agent in Charge)
 * Jessica Knight (Field Agent)
 * Dr. Donald "Ducky" Mallard (Historian & Archivist)
 * Timothy McGee (Senior Field Agent)
 * Dr. James "Jimmy" Palmer (Chief Medical Examiner)
 * Nicholas "Nick" Torres (Field Agent)
 * Leon Vance (Director)

Former

 * Eric Beal (Technical Operator)
 * Eleanor Bishop (Field Agent)
 * Ziva David (Junior Agent, resigned 2013)
 * Anthony DiNozzo (Senior Agent, retired 2016)
 * Mike Franks (Supervising Agent MCRT, retired 1996, deceased 2011)
 * Nate Getz (Operational Psychologist/Operational Liaison - Middle East)
 * Leroy Jethro Gibbs (Special Agent In Charge, retired 2021)
 * Owen Granger (Assistant Director, deceased 2017)
 * Kelsey Hill (Forensics Assistant, currently Forensic Scientist, FBI New York)
 * Peter Hill (Field Agent MCRT, later Chief of Police - Springwood, Ohio and Sheriff - Haddonfield, Illinois, deceased 2009)
 * Lauren Hunter (Acting Operations Manager OSP, deceased 2012)
 * Nell Jones (Intelligence Analyst)
 * Henrietta "Hetty" Lange (OSP Operations Manager)
 * Lara Macy (Special Agent In Charge OSP, deceased 2010)
 * Thomas Morrow (Director, currently working for Homeland Security, deceased 2016)
 * Mike Renko (Field Agent OSP, deceased 2012)
 * Abby Sciuto (Forensics, resigned 2018)
 * Jennifer Shepard (Director, deceased 2008)
 * Jacqueline Sloane (Forensic Psychologist)
 * Caitlin Todd (Field Agent MCRT, deceased 2005)
 * Dominic Vail (Field Agent OSP, deceased 2010)