The Moment That Changed ‘NCIS’ Forever Wasn't Ziva's Exit

NCIS has gone through many changes and some big ones at that. Many of the cast members left the series or went on to pursue other things after making an impact on the show. Only a few core characters have been there from the beginning or close to it. But, NCIS has been good about choosing the right people to stick around on the show, leaving audiences with numerous brilliant episodes to watch. However, one of the defining moments early on, when Caitlin "Kate" Todd (Sasha Alexander) was shot, changed the show forever.