This is a tricky one as I don't often pick favourites. For me skill as an actor or actress means that they can handle a number of different roles (ie not always comedy or romance or action) and are convincing in all of them. I don't really like him, but I respect the talents of Leonardo DiCaprio, who has switched well between his roles in What's Eating Gilbert Grape and the likes of Blood Diamond.
Julia Sawalha shows pretty good versitility when you compare her role as Saffy in Absolutely Fabulous and Lydia in the BBC's 6-part mini series of Pride and Prejudice.
This brings us round to the person who is probably my favourite actor/actress, because she was in Pride and Prejudice alongside Ms Sawalha. I have only seen a total of two movies (plus forementioned television appearance) with Jennifer Ehle in them, and I only enjoyed one of them. But I am constantly impressed with her ability to portray the thoughts and feelings of Miss Elizabeth Bennett with an expressive face and mobile eyebrows. Also, she's gorgeous. ;-)
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