"NCIS" is a popular CBS series and franchise that stands for Naval Criminal Investigative Service. The show focuses on criminal cases involving individuals from the Navy or Marine Corps. Real NCIS agents have praised the show for its portrayal of certain aspects of their work, but also acknowledge that it takes creative liberties and is not fully realistic. However, some fans feel that the show is not authentic and criticize its accuracy. Ultimately, viewers will have to form their own opinion about the show's depiction of life in the NCIS.