What's Her Best Hair?

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MEGAN FOX

The action star does a Transformers-worthy red-carpet switch-up of her own on the MTV Movie Awards red carpet in ‘09! The previous year, she had gone for stick-straight layers, but slicked back the top and let the ends trail in loose waves for this time around.

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LAUREN CONRAD

The former Hills star sends her soft waves packing, adding chunky texture and extra inches on the MTV Movie Awards red carpet.

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NICOLE KIDMAN

Bryan Bedder/Getty; Asadorian-Mejia/Splash News Online

For over a year Nicole’s made pale blonde her signature look, but the actress returns to her red roots while filming in N.Y.C.

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HAYDEN PANETTIERE

Everyone has their ups and downs – and the Heroes star takes hers in stylish stride, trying tousled waves at the Spike TV Guys Awards, then pulling her hair into a sleek updo at the MTV Movie Awards.

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TARAJI P. HENSON

Steve Granitz/WireImage; Jeffrey Mayer/WireImage

Forget that classic bob the Oscar nominee wore at the Academy Awards! For the MTV Movie Awards, the actress goes rock ‘n’ roll, cutting her hair into a choppy, spiked style.

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ASHLEY OLSEN

The designer gives a jagged edge to her long blunt bob, adding choppy long layers for a film premiere in Hollywood.

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MARION COTILLARD

Taking her look from glamorous to chic, the Oscar winner straightens her waves into a polished bob.

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MALIN ACKERMAN

The actress goes ’80s-sleek at the MTV Movie awards by slicking back her blonde hair, before going wild the next night with tousled layers for a Hollywood film premiere.

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ANNALYNNE MCCORD

It was a weekend of whirlwind beauty for the 90210 star, who attended the Chrysalis Butterfly Ball with a striking bouffant-top updo, which she traded the next night for old-school Hollywood waves at the Young Hollywood Awards in Santa Monica.

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JENNIFER LOVE HEWITT

The famously dark-haired star adds summery blonde highlights for the Monte-Carlo Television Festival.

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SELENA GOMEZ

“I cut it yesterday,” the Disney star told PEOPLE.com about her new highlighted bob. “I was sitting down in the chair, and I was going to ask for the same thing: little extensions, curling it, long.” But on the spur of the moment, she says, “I just cut it – cut it off! It feels good.”

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HEIDI KLUM

The supermodel proves just how sexy a bob can be at an event in her German homeland, before trying a summery updo at a charity event in L.A.

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BEYONCé

Mejia/Asadorian/Splash News Online; Peter Kramer/AP

For months, was all about soft waves. But she’s taking summer’s warm weather in stride with more natural, ringlet curls.

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EMILY BLUNT

The actress highlighted her chestnut locks by letting her hair down at the Sunshine Cleaning premiere, then pulled it back into a sleek ponytail to show off new red hair at a charity event in N.Y.C.

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KATHERINE HEIGL

Roger Walsh /Landov; John Shearer/WireImage

hit the premiere of The Ugly Truth with brown hair that set off her dark eyes.

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RIHANNA

Saleem Elatab-AhmadElatab/Splash News Online; Anderson/Vila/Bauer-Griffin

Taking Hollywood’s hair-shaving trend to bold new levels, debuted freshly shorn sides that added edge to her summertime look.

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CIARA

“Here’s my new haircut by Kiyah Wright!:) we teamed up!:),” the singer Tweeted this week of the short style that replaced her signature long tresses.

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MICHELLE OBAMA

entered the White House with a long, classic bob – but faked a shorter tucked-under style at a music event this week.

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MEGAN FOX

While promoting Transformers: Revenge of the Fallen in Germany, went for major sex appeal with a long slick ponytail. But for the Armani Privé couture show in Paris, the sultry star goes for Old Hollywood glam with face-framing soft curls.

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JESSICA ALBA

trades in her dark brown locks for a new tousled light blonde do.

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HAYDEN PANETTIERE

Changing hairstyles is all in a day’s work for the Heroes Panettiere starts the day with pin-straight platinum locks for an appearance on MTV, only to arrive at the evening screening of I Love You, Beth Cooper sporting loose waves and deep side part.

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JESSICA BIEL

Alberto E. Rodriguez/Getty; Alex J. Berliner/Berliner Studio/BEI

The may have spent months with honey blonde highlights in her light brown hair, but at a fashion party this week she debuted a new red tint.

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TAYLOR MOMSEN

While on set as Gossip Girl’s new Queen Bee, adds length to her signature shaggy do with long blonde extensions done in a half-up style.

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LAUREN CONRAD

The gave up her signature hairstyle for a long brown bob – but only for the day while posing for a magazine. “I got to wear a brown wig all day,” she tweeted. “It [was] fun Kinda like playing dress up.”

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KRISTEN STEWART

You might be used to seeing with tousled auburn locks, but for her new role as singer Joan Jett, Kristen dyed her hair black and went for a choppy style that shouts, “I love rock ‘n’ roll!”

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KIM KARDASHIAN

Tyrone Kerr/FilmMagic; Todd Williamson/WireImage

The hit the MuchMusic Awards with a tucked-under bob, which, she tweeted, was all about “channeling Marilyn Monroe.” But days later at a product launch party in Beverly Hills, she was back to her trademark lanky locks.

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LINDSAY LOHAN

The abandons her natural red hair for newly platinum tresses.

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SCARLETT JOHANSSON

The departed from the dark auburn hair that she wore for months and tried out a softer strawberry blonde look.

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BRITNEY SPEARS

For weeks, the rocked dark brunette locks, but quickly went back to her signature blonde.

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SOLANGE KNOWLES

Jordan Strauss/WireImage; Splash News Online

“I. just. wanted. to. be. free. from. the. bondage. that. black. women sometimes. put. on. themselves. with. hair.” the singer Tweeted after she removed the blunt-banged wig she’d worn to an event the night before and showed off a natural, closely-cropped do on the streets of L.A.

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