Inside the party, guests sipped on "Kate Hudson's Bloody Cosmos," the same Absolut Elyx cocktail the Rock the Kasbah star featured in her Snapchat videos one night earlier. Hudson went with a "Wild West" costume this year, which consisted of a thick black choker, long white skirt and a matching corset that gave her cleavage an extra boost.
Hudson's ex-fiancé, Matt Bellamy, was ready to party, stepping out in a black leather jacket and pants combo, which he paired with shiny leopard-print shoes. Judging from girlfriend Elle Evans' sexy look, it appears the two were putting a deadly spin on Sandy and Danny from Grease. Despite the fake blood on the Muse frontman's face, he proved there's certainly no bad blood between he and Hudson!
Opting for some sparkle, Nicole Richie sported an embellished gold top over matching pleather leggings for her epic Siegfried & Roy group costume. Her makeup, wig and zebra-print bow tied the fun look together perfectly.
Jessica Alba attended the bash with her close pal, Kelly Sawyer, and the two put their own silly twist on Patsy and Edina from the British sitcom Absolutely Fabulous. "#ABFAB w my boo @kellysawyer," Alba captioned a Boomerang video of the pair. "#patsyandedina #bff #Halloween."
Kendall Jenner also made her way to the soiree, turning heads in a black latex dress with a very plunging neckline. Her thigh-high tights, platform booties, space buns, choker and black-as-night lipstick gave the entire outfit a sexy goth vibe.
Like Jenner, Emma Roberts was dressed in head-to-toe black, which helped keep the focus on her flawless skeleton face paint.
And although all of the aforementioned ensembles were undoubtedly a hit, Hudson couldn't help herself from choosing a favorite. On Saturday, she took to Instagram to dub Katy Perry's Hillary Clinton costume the "best of the night."