NCIS, which stands for Naval Criminal Investigative Service, is a popular American television series that first premiered in 2003. The show follows the fictional Major Case Response Team (MCRT) of the NCIS, a federal law enforcement agency that specializes in investigating crimes involving Navy and Marine Corps personnel.
The main character of the show is Leroy Jethro Gibbs, a former Marine who now leads the MCRT. Gibbs is known for his tough, no-nonsense approach to solving cases, and his team consists of a diverse group of agents, each with their own unique skills and personalities.