The fifteenth season of the American police procedural drama NCIS premiered on September 26, 2017, in the same time slot as in the previous seasons, Tuesdays at 8 PM. The season premiere was watched by 17.42 milion viewers, picking up two months after Gibbs and McGee were last seen fighting a group of rebels in Paraguay and focued on the aftermath of those events. The season concluded on May 22, 2018 and contained 24 episodes. NCIS revolves around a fictional team of special agents from the Naval Criminal Investigative Service, which conducts criminal investigations involving the U.S. Navy and Marine Corps. The series was renewed for fourteenth and fifteenth seasons by CBS on Monday, February 29, 2016.