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Still promoting her new movie "Seeking a Friend for the End of the World", Keira Knightley made a guest appearance on "Late Night with Jimmy Fallon".
She sparkled wearing a Valentino dress from the Fall 2012 collection.
Keeping the accessories to a minimum with just a pair of black pumps, Keira let her black dress with sheer long-sleeves and embroidered silver metallic details do all the talking.
The sophisticated outfit was finished off with a classic bun, smokey eyes and glossy lips.