Heidi Klum(01 of72)
Open Image ModalHeidi Klum attends the 2013 Heidi Klum Halloween Party dressed as an elderly woman, at Marquee on October 31, 2013 in New York City. (Photo by Andrew Toth/FilmMagic) (credit:Andrew Toth via Getty Images)
Iggy Azalea(02 of72)
Open Image ModalIggy Azalea dressed as Cruella de Vil attends the VEVO Halloween showcase at The Oval Space on October 31, 2013 in London, England. (Photo by Gareth Cattermole/Getty Images) (credit:Gareth Cattermole via Getty Images)
Alessandra Ambrosio(03 of72)
Open Image ModalModel Alessandra Ambrosio, dressed as the Queen Of Hearts, attends the Casamigos Halloween Party at the home of Mike Meldman on October 25, 2013 in Beverly Hills, California. (Photo by Jerod Harris/Getty Images) (credit:Jerod Harris via Getty Images)
Chloe Moretz(04 of72)
Open Image ModalChloe Moretz sighting on October 31, 2012 in London, England. (Photo by Niki Nikolova/FilmMagic) (credit:Niki Nikolova via Getty Images)
Kim Kardashian(05 of72)
Open Image ModalKim Kardashian, dressed as Poison Ivy, attends the Midori Green Halloween costume party at Lavo on October 29, 2011 in New York City. (Photo by Rob Kim/FilmMagic) (credit:Rob Kim via Getty Images)
Scott Disick And Kourtney Kardashian(06 of72)
Open Image ModalScott Disick (dressed as Robin) and Kourtney Kardashian (Dressed As Batman) arrive at Kim Kardashian's Halloween party at LIV nightclub at Fontainebleau Miami on October 31, 2012 in Miami Beach, Florida. (Photo by John Parra/WireImage) (credit:John Parra via Getty Images)
Pink(07 of72)
Open Image ModalSinger Pink, dressed as a clown, arrives at Heidi Klum's 2008 annual Halloween party at 1OAK on October 31, 2008 in New York City. (Photo by Charles Eshelman/FilmMagic) (credit:Charles Eshelman via Getty Images)
Bethenny Frankel(08 of72)
Open Image ModalBethenny Frankel, dressed as Marilyn Monroe, attends Heidi Klum's Halloween presented by Shutterfly at Marquee on October 31, 2013 in New York City. (Photo by Andrew H. Walker/Getty Images for Shutterfly) (credit:Andrew H. Walker via Getty Images)
Dascha Polanco(09 of72)
Open Image ModalActress Dascha Polanco, dressed as the Black Swan, attends Shutterfly Presents Heidi Klum's 14th Annual Halloween Party sponsored by SVEDKA Vodka and smartwater at Marquee on October 31, 2013 in New York City. (Photo by Cindy Ord/Getty Images for Heidi Klum) (credit:Cindy Ord via Getty Images)
June Ambrose(10 of72)
Open Image ModalStylist June Ambrose, dressed as Queen Elizabeth, attends the 2013 Heidi Klum Halloween Party at Marquee on October 31, 2013 in New York City. (Photo by Andrew Toth/FilmMagic) (credit:Andrew Toth via Getty Images)
Shanina Shaik(11 of72)
Open Image ModalModel Shanina Shaik, dressed as Princess Jasmine attends the 2013 Heidi Klum Halloween Party at Marquee on October 31, 2013 in New York City. (Photo by Andrew Toth/FilmMagic) (credit:Andrew Toth via Getty Images)
Alexa Chung(12 of72)
Open Image ModalAlexa Chung, dressed as Marie Antoinette, attends the Browns Focus Halloween party hosted by Alexa Chung at St Banabas House in Soho on October 31, 2008 in London, England. (Photo by Dave M. Benett/Getty Images) (credit:Dave M. Benett via Getty Images)
Anne Hathaway(13 of72)
Open Image ModalActress Anne Hathaway, dressed as Cleopatra, attends Heidi Klum's 5th Annual Halloween party at Marquee October 31, 2004 in New York City. (Photo by Evan Agostini/Getty Images) (credit:Evan Agostini via Getty Images)
Fergie And Josh Duhamel (14 of72)
Open Image ModalDressed as sexy Elvira and a ghastly ghoul (credit:X17)
Heidi Klum(15 of72)
Open Image ModalHeidi Klum arrives at her 12th Annual Halloween Party in Las Vegas. (2011) (credit:Getty)
Michelle Trachtenberg(16 of72)
Open Image ModalActress Michelle Trachtenberg attends Heidi Klum's annual Halloween party at the Dream Hotel on Monday, Oct. 31, 2011 in New York. (AP Photo/Evan Agostini) (credit:AP)
Paulina Gretzky(17 of72)
Open Image Modal (credit:Paulina Gretzky/Twitter)
Stacy Ferguson(18 of72)
Open Image ModalSinger Stacy "Fergie" Ferguson attends Heidi Klum's annual Halloween party at the Dream Hotel on Monday, Oct. 31, 2011 in New York. (AP Photo/Evan Agostini) (credit:AP)
Heidi Klum(19 of72)
Open Image ModalHeidi Klum, dressed as Cleopatra, attends her Haunted Holiday Party benefiting Superstorm Sandy relief efforts, on Saturday, Dec. 1, 2012 in New York. Klum's original party, scheduled to be held on Halloween, was postponed due to the storm. (Photo by Charles Sykes/Invision/AP) (credit:AP)
Heidi Klum, Seal(20 of72)
Open Image ModalModel and television personality Heidi Klum, left, and husband Seal attend Heidi Klum's annual Halloween party at the Dream Hotel on Monday, Oct. 31, 2011 in New York. (AP Photo/Evan Agostini) (credit:AP)
Kim Kardashian(21 of72)
Open Image Modal Kim Kardashian attends 2nd Annual Midori Green Halloween Party at Avenue on October 27, 2012 in New York City dressed as a mermaid. (credit:Getty Images)
Katy Perry (22 of72)
Open Image ModalKaty Perry as Jane Lane and Shannon Woodward as Daria. (credit:Katy Perry/Twiiter)
Kate Upton(23 of72)
Open Image ModalModel Kate Upton attends Heidi Klum's annual Halloween party at the Dream Hotel on Monday, Oct. 31, 2011 in New York. (AP Photo/Evan Agostini) (credit:AP)
Debra Messing(24 of72)
Open Image Modal"HAPPY HALLOWEEN!! Me and Mariska starting the night!! #boo," the "Smash" star tweeted Wednesday. (credit:Debra Messing/Twitter)
Darren Criss(25 of72)
Open Image ModalDarren Criss is a boy scout and probably a big fan of "Moonrise Kingdom." (credit:PacificCoastNews)
Jenni 'JWoww' Farley, Roger Mathews(26 of72)
Open Image ModalWe never thought we'd say it, but the "Jersey Shore" star and her fiancé positively geeked it out. (credit:PacificCoastNews)
Christina Milian (27 of72)
Open Image ModalNo sleight of hand here. Christina Milian is the Queen of Hearts. (credit:PacificCoastNews)
Stacy Keibler(28 of72)
Open Image ModalGeorge Clooney's girlfriend is "Black Swan." (credit:PacificCoastNews)
Tish Cyrus, Brandi Cyrus(29 of72)
Open Image ModalPop starlet Miley Cyrus' mum and sister Tish Cyrus and Brandi Cyrus are all dressed up for Halloween as they head to the Roosevelt hotel for a party in Hollywood. (credit:PacificCoastNews)
Sacha Baron Cohen(30 of72)
Open Image ModalSacha Baron Cohen donned a bizarre monkey-cow costume. (credit:FameFlynet)
P. Diddy(31 of72)
Open Image ModalP. Diddy rocked out at the Playboy Mansion Halloween Party in Beverly Hills, California on October 27th, 2012. (credit:FameFlynet)
Brandon Davis(32 of72)
Open Image ModalBrandon Davis at the Playboy Mansion Halloween Party in Beverly Hills, California on October 27th, 2012. (credit:FameFlynet)
Lucy Hale(33 of72)
Open Image ModalLucy Hale as a unicorn. (credit:Lucy Hale/Twitter)
Shenae Grimes, Chris March(34 of72)
Open Image ModalIn this Image released by Mattel, actress Shenae Grimes, from the series "90210", left, has a fitting of her Monster High Frankie Stein Halloween costume created by "Project Runway" alum Chris March, Wednesday, Oct. 17, 2012, in El Segundo, Calif. Grimes will be attending "Glee" cast member Matthew Morrison's 3rd Annual Halloween Bash, dressed as Frankie Stein, daughter of Frankenstein, from the popular Monster High franchise. This year, the popular Halloween party will be sponsored by Monster High. (AP Photo/Mattel, Rene Macura) (credit:AP)
Heidi Klum (35 of72)
Open Image Modal Heidi Klum gets fitted for her 13th annual Halloween party at finale sponsored by HobNob Wines, Svedka Vodka And Smartwater on September 3, 2012 in New York City. (credit:Getty Images)
Sarah Hyland(36 of72)
Open Image ModalSarah Hyland as Spinelli from "Recess." (credit:Sarah Hyland/Twitter)
Nicole Scherzinger(37 of72)
Open Image ModalNicole Scherzinger as a vampire. (credit:James Curley/Coalition Pictures)
Kim Kardashian(38 of72)
Open Image ModalKim Kardashian as a leopard. (credit:Kim Kardashian/Twitter)
Holly Madison(39 of72)
Open Image ModalHolly Madison as Sleeping Beauty. (credit:Holly Madison/Twitter)
Fergie(40 of72)
Open Image ModalFergie as Lindsay Lohan. (credit:Fergie/Twitter)
Christina Milian(41 of72)
Open Image ModalChristina Milian as Sulley. (credit:Christina Milian/Twitter)
Fergie & Josh Duhamel(42 of72)
Open Image ModalFergie & Josh Duhamel as Angelyne & Dennis Woodruff. (credit:FameFlynet)
Christina Aguilera(43 of72)
Open Image ModalChristina Aguilera as ??? (credit:Pacific Coast News)
Paris Hilton(44 of72)
Open Image ModalParis Hilton as Alice. (credit:X17Online)
Kris Jenner(45 of72)
Open Image ModalKris Jenner as Wonder Woman. (credit:Kris Jenner/Twitter)
Ashley Benson(46 of72)
Open Image ModalAshley Benson as Tweedle Dee (or Dumb). (credit:Ashley Benson/Twitter)
Hugh Hefner(47 of72)
Open Image ModalHugh Hefner as a vampire. (credit:Hugh Hefner/Twitter)
Holly Madison(48 of72)
Open Image ModalHolly Madison as the Cheshire Cat. (credit:Holly Madison/Twitter)
Jessica Alba, Cash Warren, & Honor Warren(49 of72)
Open Image ModalThe Incredibles (credit:Jessica Alba/Twitter)
Lauren Conrad(50 of72)
Open Image Modal (credit:Lauren Conrad/Twitter)
Hilary Duff(51 of72)
Open Image ModalHilary Duff in a Día de los Muertos costume. (credit:Hilary Duff/Twitter)
Kim Kardashian(52 of72)
Open Image ModalKim Kardashian as Kris Jenner. (credit:Kim Kardashian/Twitter)
Fergie(53 of72)
Open Image ModalFergie as a sexy cat. (credit:Fergie/Twitter)
Ryan Seacrest & Julianne Hough(54 of72)
Open Image ModalBonnie & Clyde (credit:Julianne Hough/Instagram)
Julie Bowen(55 of72)
Open Image ModalJulie Bowen as a scary Bo Peep. (credit:Julie Bowen/WhoSay)
Genevieve Jones & Nicky Hilton (56 of72)
Open Image ModalGenevieve Jones & Nicky Hilton as a KISS member and a leopard. (credit:Genevieve Jones/Twitter)
Adam Lambert(57 of72)
Open Image ModalAdam Lambert as a vampire. (credit:Adam Lambert/Twitter)
Chord Overstreet(58 of72)
Open Image Modal (credit:Chortd Overstreet/Twitter)
Heidi Montag & Crystal Harris (59 of72)
Open Image Modal (credit:Heidi Montag /Twitter)
Jesse McCartney(60 of72)
Open Image Modal (credit:Jesse McCartney/Twitter)
Diddy & Holly Robinson Peete(61 of72)
Open Image ModalAs Prince. (credit:Holly Robinson Peete/Twitter)
Bella Thorne(62 of72)
Open Image ModalBella Thorne as a vampire bride. (credit:Bella Thorne/Twitter)
Liam Payne(63 of72)
Open Image ModalLiam Payne as Batman. (credit:Liam Payne/Twitter)
Shanae Grimes(64 of72)
Open Image ModalShanae Grimes as a skeleton. (credit:Josh Beech/Twitter)
Scott Disick(65 of72)
Open Image ModalScott Disick as Patrick Bateman. (credit:Getty Images)
Nicole Richie(66 of72)
Open Image ModalNicole Richie and friends as Wilderness Girls from "Troop Beverly Hill." (credit:Nicole Richie/Twitter)
Bill Murray(67 of72)
Open Image ModalBill Murray backstage during the Crossroads Guitar Festival in Bridgeview, Illinois. (2010) (credit:Getty)
Roberto Cavalli(68 of72)
Open Image ModalDesigner Roberto Cavalli attends his Halloween Party at Cipriani's in New York City. (2007) (credit:Getty)
Pierce Brosnan(69 of72)
Open Image ModalActor Pierce Brosnan attends Allison Sarofim's Halloween Party. (2010) (credit:Getty)
Marc Jacobs(70 of72)
Open Image ModalMarc Jacobs (left) and Valentino Garavani attend Allison Sarofim's 80s-themed Halloween party. (2009) (credit:Getty)
Padma Lakshimi(71 of72)
Open Image ModalPadma Lakshimi attends Allison Sarofim's 2010 Halloween Party. (2010) (credit:Getty)
Nina Garcia(72 of72)
Open Image ModalNina Garcia attends Allison Sarofim's 80s-themed Halloween party. (2009) (credit:Getty)