There are some changes coming to the upcoming season of NCIS, which is about to be in its 21st season.

Many of the fan favorite stars are still part of the show, including David McCallum‘s Dr. Donald “Ducky” Mallard, however, there are a handful of stars who have left the show over the 20 seasons.

We’re taking a deep dive into just why the actors left the show, and some of the reasons include boredom, the insane working schedule, and more.

CBS confirmed that NCIS officially returns for Season 21 on Monday, February 12, 2024 at 9 p.m. ET!

Head inside to find out the reasons why all the main characters from NCIS left the show…