Vote! Natural vs. Hair Extensions

Presto, change-o – it's an instant makeover. Tell us what you think of the stars' lengthier looks – then see the results in PEOPLE's Fall StyleWatch issue, on newsstands Aug. 4. By Serena Kappes

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KEIRA KNIGHTLEY

"You can change your look for the night and not have your hair damaged," says Knightley's stylist Adir about using clip-on extensions on the Pirates of the Caribbean actress.