Heidi Klum Dresses As Jessica Rabbit

Heidi Klum attends her Halloween Party on Oct. 31, 2015 in New York City.
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Casper Smart and Jennifer Lopez

Casper Smart and Jennifer Lopez attend Heidi Klum's 16th Annual Halloween Party sponsored by GSN's Hellevator And SVEDKA Vodka At LAVO New York on Oct. 31, 2015 in New York City.
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Cindy Crawford and Rande Gerber

Cindy Crawford and Rande Gerber arrive at the Casamigos Tequila Halloween Party on Oct. 30, 2015 in Los Angeles, Calif.
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Fergie and Josh Duhamel

Fergie and Josh Duhamel are seen celebrating Halloween in Beverly Hills on Oct. 30, 2015 in Los Angeles, Calif.
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Nicki Minaj

Recording artist Nicki Minaj attends a Haunted Funhouse Halloween party at 1 OAK Nightclub at The Mirage Hotel & Casino on Oct. 31, 2015 in Las Vegas, Nevada.
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David Spade

David Spade arrives at the Casamigos Tequila Halloween Party on Oct. 30, 2015 in Los Angeles, Calif.
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John Stamos and Josh Peck

John Stamos and Josh Peck attend Carlton's Halloween Nightmare! on Oct. 24, 2015 in Beverly Hills, Calif.
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Ellen DeGeneres Dresses as a Kardashian

The Ellen Show posted this photo to Instagram on Oct. 29 with the caption, "Don't miss my Halloween show tomorrow! Love, Karla Kardashian."
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Nick Jonas

Nick Jonas attends the Maxim Halloween Party Presented By Karma International, Oct. 24, 2015, in Los Angeles.
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Colton Haynes

Colton Haynes shared this image to his Instagram dressed as Ursula from "The Little Mermaid."
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Niecy Nash

Niecy Nash arrives at the 2015 MAXIM Magazine's official Halloween Party held, Oct. 24, 2015, in Beverly Hills, Calif.
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Aubrey O'Day

Aubrey O'Day arrives at the 2015 MAXIM Magazine's official Halloween Party held, Oct. 24, 2015, in Beverly Hills, Calif.
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Peta Murgatroyd & Maksim Chmerkovskiy

Peta Murgatroyd, right, and Maksim Chmerkovskiy arrive at the 2015 MAXIM Magazine's official Halloween Party held, Oct. 24, 2015, in Beverly Hills, Calif.
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AnnaLynne McCord

AnnaLynne McCord hosts Carlton's Halloween Nightmare!, Oct. 24, 2015, in Beverly Hills, Calif.
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Bai Ling

Bai Ling as The Joker, attends the Halloween Hotness 2.0 Costume Party to benefit The National Breast Cancer Foundation held at the Hollywood Roosevelt Hotel, Oct. 17, 2015, in Hollywood, Calif.
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Heidi Klum

Heidi Klum attends Moto X presents Heidi Klum's 15th Annual Halloween Party sponsored by SVEDKA Vodka at TAO Downtown, Oct. 31, 2014, in New York City.
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Miley Cyrus

Miley Cyrus shared this image to her Twitter dressed as Lil' Kim for Halloween.
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Katie Perry

Katie Perry is seen at Kate Hudson's annual Halloween party, Oct. 30, 2014, in Los Angeles.
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Adam Lambert

Adam Lambert arrives at Adam Lambert's 2nd Annual Halloween Bash at Bootsy Bellows, Oct. 31, 2014, in West Hollywood, Calif.
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