The Devil Wears Prada star's dress had a sheer top that made it sexy without in any way detracting from its elegance.
Blunt, 27, accessorized with nude peep toe heels. Dark red lip color, light makeup and jewelry added to her allure.
Blunt, who is married to American actor John Krasinski, chatted with fans and signed autographs.
Inspired by William Shakespeare's Romeo and Juliet, the films features two garden gnomes in forbidden love; they seek love and happiness but are caught in the midst of a feud between neighbors. This film's two main characters are voiced by James McAvoy and Emily Blunt. The film releases in theatres on February 11.