Morena Baccarin-
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Morena Baccarin is something of a staple in Nerdom (I'm not calling all Tolkien fans nerds... pff, nerds...) popping up in everything from
Firefly, Justice League cartoons,
Stargate, DC-TV, and most recently the
Deadpool movie. The always beautiful Ms. Baccarin can bring just as much of a dark and sexy nature to Ungoliant as her fellow nominees. But Morena Baccarin brings something else: that spider-like physicality and gaze that makes you not quite sure whether you want to fight her off or run in terror or fall in love.
Morena also has a lot of experience in playing both heroines and villainesses. I think her comfort in either type of role would help bring an ambiguity to Ungoliant and her intentions. Think it would be fun to toe-the-web so to speak. She could turn a seemingly one-dimensional, evil spider into a more rounded, interesting character.
EDIT: WAS CHOSEN; OK BY EXECS