Photos: Celebs dress up for Halloween

  • AnnaLynne McCord channeled the Victorian era to host a Halloween party in Las Vegas
  • Michelle Trachtenberg brought Tim Burton's "Blue Girl With Wine" artwork to life
  • Christina Aguilera played a pirate at Maroon 5's Hollywood bash

(InStyle) -- Need some Halloween costume inspiration? See how your favorite celebrities celebrate the most frightful night of the year:

Kim Kardashian "Poisonous!!!" the reality star Tweeted of her Poison Ivy outfit.

Alyson Hannigan The actress played the role of a scarecrow, while daughter Satyana dressed as a pumpkin.

AnnaLynne McCord The actress channeled the Victorian era to host the Haunted Seduction Halloween party held at Pure Nightclub in Las Vegas.

Michelle Trachtenberg The actress brought Tim Burton's "Blue Girl With Wine" piece of artwork to life in New York.

Fergie With teddy bear, trophy, sash, and tiara in hand, the singer played the perfect toddler beauty queen at Heidi Klum's Halloween bash at PH-D at Dream Downtown in New York.

Dita Von Teese The burlesque star pulled a piece out of her closet for Maroon 5's Hollywood Halloween. "Last minute decision to go out for Halloween...Scraping through my wardrobe for something that resembles a costume. No problem!" she Tweeted of her emergency costume.

Christina Aguilera "The Voice" judge played a pirate at Maroon 5's Hollywood bash.

Leona Lewis The singer represented a tragic pageant queen, sash and all.

Lauren Conrad The reality-star-turned-fashion-designer reworked a cute red and white polka dot dress into a Minnie Mouse costume.

Miranda Kerr The Victoria's Secret Angel stepped into the ring at Catch Rooftop in New York City to host a bash as a circus ringmaster.

See 51 more celebrities in Halloween costumes!

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