Sasha Alexander – Caitlin Todd
On the original cast list is the name of the lovely actress Sasha Alexander, who has been a part of the series since its inception. Unfortunately, she would leave the show in its second season, claiming that she was working too much! After leaving NCIS, Sasha landed her own popular program, the cop drama Rizzoli & Isles, and has also featured on Law & Order: SVU, Curb Your Enthusiasm, and Shameless.
Jennifer Esposito – Alex Quinn
Jennifer Esposito is an American actress best recognized for her work on television rather than film, but she has appeared in a number of significant films. In addition to Law and Order: SVU, Blue Bloods, and Awkwafina Is Nora from Queens, she has acted in the films Crash, Taxi, and Summer of Sam. How could we forget that she also featured on NCIS, albeit for a brief yet memorable time? She joined the cast as Alex Quinn in 2016, but before the end of the season, her character had been killed off.