Kim Kardashian Rocks A Poison Ivy Costume For Halloween

Watch out Uma Thurman! Kim Kardashian hosted the Midori Melon Green Halloween Party at the Lavo nightclub in New York City on Saturday dressed to kill as Batman villain Poison Ivy!

We think Kim looked fantastic as the temptress, who last brought the dynamic duo to their knees in Batman And Robin, and might even rival supermodel Heidi Klum's costume this year.

Heidi even Tweeted Kim earlier Saturday while she was putting the finishing touches on her makeup for the night.

"@kimkardashian I think I look sexier than you tonight!! ;)" she wrote.

Kim was able to cast her spell on her best friend/PR guru Jonathan Cheban, who dressed as the Caped Crusader's companion, Robin; but husband Kris Humphries was nowhere to be found.

Earlier in the day Kim Tweeted a pair of photos while getting into costume.

AnnaLynne McCord Got Halloween Off To A Start Dressed As Marie Antoinette

Saturday night, Annalynne McCord of the hit television series "90210" kicked off the Halloween weekend by hosting a night of haunted seduction at PURE Nightclub inside Caesars Palace. The Hollywood starlet arrived at the mega-club along with her sisters Angel and Rachel McCord. In full Halloween spirit, the trio showed off their stunning Victorian costumes as they posed for the cameras. While on the red carpet, AnnaLynne introduced herself as Marie Antoinette for the night and even pointed out that she added a little personal flair to her costume by sewing on additional details such as the ribbons on her heels.

After posing for photos, the sisters along with their entourage were escorted inside to the VIP area located on PURE's main stage where they immediately became the center of attention. Female admirers flocked their table in hopes to meet the girls. All three McCord sisters graciously met with fans and took photos with them. As a double celebration, the evening also served as Rachel's 23rd birthday bash. In true Vegas fashion, the youngest McCord was presented with a stunning Halloween-themed birthday cake in honor of her special day. AnnaLynne and Angel joined their little sister as she made a wish and blew out her candles while the whole club cheered her on.

Later in the evening, the party really got started as the contest for "Best Costume" began with AnnaLynne as the lead judge. As a true fan of the spooktacular holiday, the gorgeous actress got really into the contest as she thought some of the costumes "were so crazy!" After multiple rounds of judging, the blonde beauty along with help from the crowd picked the top three contestants and declared the winners: first place was awarded to the "Hangover Guy," second place went to "Iron Man" also known as AnnaLynne's favorite and third place went to "Swamp Man." PURE Nightclub gave away a total of $10,000 to the winners.

Once the costume contest winners were announced, AnnaLynne rejoined her sisters to party therest of the night away. While Angel and Rachel sipped on champagne, AnnaLynne opted to drink water all evening. But that didn't stop the energetic actress from enjoying the atmosphere of the club and dancing with her sisters.

The McCord sisters started the evening with dinner at Social House inside Crystals at CityCenter where they indulged and dined on Executive Chef Peter Woo's delicious Pan-Asian cuisine.

Snooki Celebrates Halloween In Las Vegas As A Sexy Leopard (Pics)

Everyone's favorite Jersey Shore star Nicole "Snooki" Polizzi took Sin City by storm as she hosted a spine-chilling Halloween bash at PURE Nightclub inside Caesars Palace. The petite guidette along with her best friend Caitlin Ryder aka "Ryder" arrived at the mega-club just before midnight looking feisty and fierce in their feline costumes. Polizzi was dressed as a sexy leopard decked out head-to-toe in fur complete with paws and tail. In addition, the energetic brunette was covered in body paint and completed the look with a set of cat eye contact lenses. In full Halloween spirit, the 23-year-old MTV reality darling growled at the cameras as she posed for photos on the red carpet.

Known for drawing a crowd wherever she goes, Polizzi was instantaneously surrounded by fans as she was being escorted inside the nightclub. Hundreds of admirers screamed and shouted "I Love You Snooki" as she made her through the venue and to her VIP table. Once she settled into her area, Polizzi rushed to the front of the stage and immediately became the center of attention. Getting the party started off right, she pumped up the crowd by shaking her tail (literally) and throwing large lighted foam batons into the sea of club goers. She got on the mic and said, "thank you everyone for coming out tonight to my favorite club in Vegas!"

Later in the evening, Polizzi played her role as celebrity guest judge in search for the "Sexiest Vixen." One-by-one the gorgeous contestants strutted their way to the main stage as they showed off their bewitching costumes for Polizzi. The competition was close as she thought all the girls looked hot and couldn't decide, but with help from the crowd the fist pumping party girl picked "Sexy Elvis" as the first place winner, followed by the "Black Angel" in second and the "Three Musketeers" in third place.

After judging the contest, Polizzi continued to party with fans as she spent the rest of the evening sipping on cocktails and dancing.

Rose McGowan Is A Sexy Musketeer

Rose McGowan attended the L.A. Gay & Lesbian Center's Annual "Halloweenie" party in Hollywood over the weekend. She looked like a member of the three musketeers.

The actress is working on several upcoming films, including "Napa," "The Tell-Tale Heart" and "Fortune."

She will also appear in the made-for-television Lifetime movie "The Pastor's Wife" based on the real-life 2006 media sensation where Mary Winkler murdered her small-town preacher husband.

A Smiling Hilary Duff Steps Out Without Make-Up

We spotted a barefaced Hilary Duff leaving her pilates class in Los Angeles with a smile and showing off her growing pregnant belly.

The actress hasn't let pregnancy slow her down. She's been busy doing a book signing tour promoting her new novel, "Elixir," a sequel to her first novel "Devoted."

She stars in the upcoming film "She Wants Me" about a neurotic writer who gets into a tricky situation when an A-list actress shows interest in the role intended for his girlfriend.

2011 American Music Award Winners

Singer Katy Perry (R) accepts a special achievement American Music Award from model Heidi Klum onstage at the 2011 American Music Awards held at Nokia Theatre L.A. LIVE on November 20, 2011 in Los Angeles, California.