The twenty-first season of the American police procedural television drama series NCIS was announced on February 21, 2023, by CBS, and premiered on February 12, 2024, and concluded on May 6, 2024. This is the first season not to feature David McCallum (as Dr. Donald "Ducky" Mallard), who died on September 25, 2023, though he is still credited in the first two episodes. Wikipedia