Jennifer Aniston (49) found fame playing Rachel Green in THE cult sitcom of the last century, Friends. She is still a highly successful actress, but also works as a film producer and director nowadays. In spite of her achievements however, Jen has not always been able to get all the roles she has wanted.

Attractive Aniston was more than interested in playing Caitlin "Kate" Todd in the crime series NCIS, but production of the series would have had to have been postponed until the final series of Friends had been filmed and so Jennifer could not take on the much-coveted role. 

Sasha Alexander (45) bagged the role instead and played Special Agent Kate from the very first episode until the end of the second series. Sasha is a very successful actress today, even though her character died at the end of season two. Safe to say, she left a lasting impression!

Diona Reasonover currently stars on NCIS  as forensic scientist "Kasie Hines".

Replacing Pauley Perrette was big shoes to fill...

'NCIS': Has Diona Reasonover Won Over The Fans By Now?