Fashion flashback!

When Jessica Chastain hit the red carpet at the premiere of The Help in Los Angeles on Tuesday, style critics experienced a bout of deja vu.

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The up-and-coming actress, 30, wore a magenta strapless Oscar de la Renta gown with vibrant turquoise earrings. And while the color combo was eye-catching, her overall look was nearly identical to the Christian Dior dress and Fred Leighton jewels Cameron Diaz, 38, donned at the Costume Institute Gala back in 2007.

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And Chastain isn't the only celeb taking style inspiration from the Bad Teacher actress. Sofia Vergara, 39, went for a similar effect at The Smurfs world premiere in New York City last month, where she rocked a purple strapless Missoni dress and large turquoise earrings by Lorraine Schwartz.

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