Oscar Fashion: Jessica Chastain Rules the Red Carpet in Alexander McQueen (Poll)

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Jessica Chastain didn't wear Armani, as many fashion critics had thought she would. We love a red-carpet surprise!

The Help star Jessica Chastain has had her hands full with fashion changes during this awards season. She's been out and about so much in the past few months and has always looked amazing, thanks in part to her stylist, Elizabeth Stewart.

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But her Oscar gown -- from the British fashion house of Alexander McQueen -- has turned the actress into the Queen of Oscar Night.

She rocked an elaborate -- almost medieval -- strapless black gown with gold brocade scrollwork and more than $2 million worth of Harry Winston yellow diamonds. Oh, and some extra hair for a fairy-princess feel.

The actress brought along her grandmother Marilyn as her date. Granny was a big fan of the book The Help (her book club had read it), and she advised Jess to take the role.

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This regal gown is definitely fit for a queen. Now all she needs is a gold Oscar statue to act as her royal sceptre.