They went from “Kate” Todd, NCIS agent, to Ziva David, Mossad exchange officer...I would tell you how it happened, but don’t want to spoil it for you. IIRC, Kate Todd was with the show the first one or two seasons...
Athough Dr Donald Mallard always called her Caitlin.
Oh, BTW...(Sheepish grin) I found out why I thought thaty they had surrepticiously replaced caitlin with Ziva...When I was DLing, I went from DLing Saeson 2 Episode 1...2..3..to DLing Season 5, episode 4...5...6.. Augggggghhhh!
Didn’t catch on till I watched the relevant episodes during the marathon.....”Duhhhhhh Which way did he go George? Which way did he go?????”