Stars in Halloween Costumes

Classy Cleopatra made an appearance in the form of Anne Hathaway at Heidi Klum's 2004 Halloween Party at New York City night spot Marquee.

-With reporting by Maggie Chong

Paris Hilton

and sister Nicky hit the pre-Halloween party circuit in Hollywood, where they stopped by the Playboy Mansion, hit hot spot Winstons, and ended the night at a private house party that lasted way past the witching hour.

Teri Hatcher

played the Queen of Hearts to daughter Emerson Tenney's Alice in Wonderland at the 2007 Dream Halloween Under The Big Top event in Santa Monica. Jamie Lee Curtis (not pictured) was ringmaster for the circus-themed party, which benefited the Children Affected by AIDS Foundation.

The Hills

star Audrina Patridge welcomed singer Christina Milian to the Hpnotiq Halloween Party at Hollywood night spot Les Deux. Patridge channeled an early Madonna for the bash, while Christina took her inspiration from Marie Antoinette.

For the 7th Annual Heidi Klum Halloween bash, held at Privilege in L.A.,Seal dressed as Eve (of Adam and Eve), while Klum was the serpent and the apple from the Garden of Eden.

Mischa Barton

donned a flirtatious Can-Can costume for The SKYY Orange Halloween Party in 2004 at Joseph's Cafe.

In 2006, Halloween aficionados Christina Aguilera and husband Jordan Bratman hit the Ghoulin Rouge party New York City dressed as a corpse bride and her ghastly groom.

Gwyneth Paltrow

and daughter Apple went trick-or-treating in their New York City neighborhood in 2006. Gwyneth got into the spirit of Halloween by wearing a bunny mask while carrying an Alice in Wonderland-clad Apple.

Chris Klein

and Ginnifer Goodwin hit the Art of Elysium Halloween Ball in Beverly Hills together, though they weren't exactly a matched set: Klein dressed as a slice of pepperoni pizza, while Goodwin went as a cauldron-carrying witch.

Eva Longoria and Mario Lopez paired up as friendly felines for a Hollywood Halloween party in 2006.

Enchanting Mariah Carey was the queen of the sea when she dressed up as a mermaid for her London Halloween party in 2003.

Haylie

and Hilary Duff were a blast from the past at Airparty Hollywood's benefit for the Trevor Project in L.A. Haylie went as an '80s aerobics instructor; Hilary dressed as a gypsy.

Always the life of the party, P. Diddy attended Mariah Carey's annual Halloween party in 2004 as a courageous centurion.

Scarlett Johansson looked a little worse for the wear leaving a spooky N.Y.C. bash at Bungalow 8 in 2005. Happily, the bullet hole in Johansson's head was just part of her costume.

Do-gooder Jerry O'Connell came as lovable Elmo to the Camp Ronald McDonald for Kids 14th Annual Family Halloween Carnival last year in L.A.