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Pop singer Rihanna is named Queen of the West Hollywood Halloween Carnaval by the City of West Hollywood in celebration of Halloween 2012 at a Halloween party at Greystone Manor Supperclub on Oct. 31, 2012, in West Hollywood, Calif.
Personal Photo/Twitter
Country singer Miranda Lambert went as Honey Boo Boo for Halloween, tweeting: "We should both win Supreme titles!"
Ke$ha/Personal Photo/Twitter
Pop singer Ke$ha gets decked out for Halloween 2012.
JenniferLopez.com
Jennifer Lopez and Casper Smart dress up as hippies for Halloween 2012.
Katy Perry/Personal Photo/Twitter
Singer Katy Perry, left, and actress Shannon Woodward dressed up as MTV animated characters, Daria and her best friend Jane Lane on Oct. 31, 2012, in Hollywood, Calif.
Selena Gomez/Personal Photo/Twitter
Selena Gomez dons a cat costume for Halloween 2012.
Chris Brown/Personal Photo/Twitter
Chris Brown and friends dressed up as Arab terrorists in beards and turbans for Halloween 2012.
Personal Photo/Twitter
Leann Rimes, posing alongside her beau Eddie Cibrian, dressed up as "Sandy" and "Danny" from the movie "Grease" for Halloween 2012.
Lady Gaga/Personal Photo/Twitter
Lady Gaga posted this Halloween photo along with the caption: "HAPPY HIGHLAWEEN!!"
Personal Photo/Twitter
Singer Pink, right, dressed up for Halloween 2012.
Avril Lavigne/Personal Photo/Twitter
Avril Lavigne tweeted this Halloween 2012 photo along with the caption: Tick or Treat... Happy Halloween! Hope everyone had a good safe night. Anchors away!"
Actor Jon Cryer poses in his costume for Halloween 2012.
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Comedian Patton Oswalt tweeted this photo along with the caption: "Mission accomplished. With a LOT of help from @donttrythis (MYTHBUSTERS' Adam Savage). #Halloween #doctorockapus"
Personal Photo/Twitter
Neil Patrick Harris, left, tweeted this Halloween 2012 photo along with the caption: "Happy Halloween everyone! Hope your tricking and treating gotcha lotsa booty! Here
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From left, the Abbey's David Cooley, recording artist Rihanna and guest attend Rihanna's Queen of the West Hollywood Halloween Carnaval at Greystone Manor Supperclub on Oct. 31, 2012, in West Hollywood, Calif.
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Kristin Cavallari hosts the Bing It On Halloween Costume Challenge at Spirit Halloween on Oct. 19, 2012, in New York.
Christopher Polk/Getty Images for Mattel
"90210" star Shenae Grimes, dressed as Monster High's Frankie Stein, leaves for Matthew Morrison's 3rd Annual Halloween Party on Oct. 28, 2012, in Los Angeles.
Lady Antebellum/Personal Photo/Twitter
Lady Antebellum tweeted this photo for Halloween 2012, along with the caption: "Happy Halloween! Love, Brooks Dunn and Reba."
Personal Photo/Twitter
Kings of Leon's Jared Followill poses with his model wife, Martha, for Halloween 2012.
Jessica Simpson/Personal Photo/Twitter
Jessica Simpson, Eric Johnson and Baby Maxwell get dressed up for Maxwell's first Halloween.
Miley Cyrus/Personal Photo/Twitter
Miley Cyrus, right, dressed up as rapper Nicki Minaj, for Halloween 2012.
Personal Photo/Twitter
Boy band One Direction posted this Halloween 2012 photo on Twitter.
Personal Photo/Twitter
Actor Chris Colfer went to the set of "Glee" in his Halloween costume on Oct. 31, 2012.
Ellen/Warner Bros.
Ellen Degeneres, left, dresses up as actress Sofia Vergara, right, for her Halloween 2012 show.
Heidi Klum/Personal Photo/Twitter
Model Heidi Klum, dressed as Cleopatra, gets her costume ready a week before Halloween. She ended up canceling her annual Halloween bash because of Superstorm Sandy.
Matthew Morrison/Personal Photo
"Glee" star Darren Criss, far left, stands next to fellow "Glee" star Matthew Morrison, dressed as Justin Timberlake, in Los Angeles.
Charles Sykes
Kim Kardashian hosts the 2nd Annual Midori Green Halloween Party on Oct. 27, 2012, in New York.
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Actress/model Stacy Keibler arrives at Hyde Bellagio at the Bellagio to host a Halloween masquerade party on Oct. 27, 2012, in Las Vegas.
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Actress Jaime Pressly with son Dezi James Calvo, left, and guest attend EBMRF & Sony PlayStation's Epic Halloween Bash hosted by James Marsden and Courteney Cox on Oct. 27, 2012, in Los Angeles.
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Actress/model Stacy Keibler hosts a Halloween masquerade party at Hyde Bellagio at the Bellagio on Oct. 27, 2012, in Las Vegas.
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Author and televison host Padma Lakshmi attends 11th Annual Dream Halloween at Hard Rock Cafe, Times Square, on Oct. 21, 2012, in New York.
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Musician Prince Malik attends 2nd Annual Midori Green Halloween Party at Avenue on Oct. 27, 2012, in New York.
Dave Kotinsky
Kim Kardashian attends the 2nd Annual Midori Green Halloween Party at Avenue on Oct. 27, 2012, in New York.
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Actress/singer Sabrina Bryan attends the 2012 'Dream Halloween' presented by Keep A Child Alive at Barker Hangar on Oct. 27, 2012 in Santa Monica, Calif.
Kim Kardashian/Personal Photo/Instagram
Kim Kardashain and Kanye West get ready for the 2nd Annual Midori Green Halloween Party at Avenue on Oct. 27, 2012, in New York.
Lucy Hale/Personal Photo/Twitter
Singer/actress Lucy Hale dresses up as a unicorn for Halloween 2012.
Diddy/Personal Photo/Twitter
Sean "Diddy" Combs tweeted this Halloween 2012 photo on Oct. 28 along with the caption: "Check dis out!! RT @CassieSuper: Cleopatra & Prince! Happy Halloween!!!!"
Liam Payne/Personal Photo/Twitter
Actor Liam Payne dresses up as Batman for Halloween 2012.
Brad Barket/Getty Images
Singer Cody Simpson, left, and Padma Lakshmi attend 11th Annual Dream Halloween at Hard Rock Cafe, Times Square on Oct. 21, 2012, in New York.
David Burtka/Personal Photo/Twitter
Neil Patrick Harris, left, spends Halloween 2012 with his longtime partner, David Burtka, right.
Christopher Polk/Getty Images for Mattel)
"90210" star Shenae Grimes, dressed as Monster High's Frankie Stein, leaves for Matthew Morrison's 3rd Annual Halloween Party on Oct. 28, 2012, in Los Angeles.
Aubrey O'Day/Personal Photo/Twitter
Singer Aubrey O'Day dresses up for Halloween 2012, tweeting: "Made my entire Native American look... feather by feather."
Christina Milian/Personal Photo/Twitter
Singer Christina Milian gets dolled up for Halloween 2012.
Ryan Seacrest/Personal Photo/Twitter
Ryan Seacrest tweeted this photo of him and girlfriend Julianna Hough, right, dressed up bank robbers Bonnie and Clyde, portrayed by Warrren Beatty and Faye Dunaway in a movie scene on right.
Rachel Zoe/Personal Photo/Twitter
Fashion stylist Rachel Zoe, dressed as a flapper, poses with Rodger Berman for Halloween 2012.
Kyle Richards/Personal Photo/Instagram
"Real Housewives of Beverly Hills" star Kyle Richards, right, attends a Halloween benefit in Los Angeles on. Oct. 28, 2012.
Chris Colfer/Personal Photo/Twitter
"Glee" star Chris Colfer tweeted this Halloween 2012 photo, along with the caption: "Happy Halloween! Hooves crossed I'm the only one dressed as a llama assassin."
Personal Photo/Twitter
Avril Lavigne's ex-husband, Sum-41's Deryck Whibley, dressed up as Lavigne for Halloween 2012. Whibley's current girlfriend, Ari Cooper, dressed up as Lavigne's new fiance, Chad Kroeger, frontman of Nickelback.
