The Naval Criminal Investigative Service (NCIS) is a federal law enforcement agency that investigates crimes involving the United States Navy and Marine Corps. Its primary mission is to protect personnel, assets, and information related to the Department of the Navy. NCIS agents work on a variety of cases, including theft, fraud, and terrorism, ensuring the safety and security of military members and their families. In addition to criminal investigations, NCIS also focuses on counterintelligence and cyber threats. The agency collaborates with other law enforcement organizations and intelligence agencies to address complex issues that may affect national security. Through its efforts, NCIS plays a vital role in maintaining the integrity of the U.S. military.