On Friday night, a ton of celebrities attended the annual Casamigos Halloween Party in Los Angeles -- where they all showed off some pretty impressive get ups.
Michelle Trachtenberg arrived as The Black Dahlia, sporting some throwback hair, a blue dress and some gruesome scars on her face.
Hilary Duff showed up with a glittery masquerade mask and crown, but made headlines for walking in with estranged hubby Mike Comrie. The two were seen holding hands -- see that photo in the gallery above.
And then there's Paris Hilton, who brought a sexy spin to Minnie Mouse, and Brittny Gastineau, who showed some insane cleavage as a zombie. Other stars in attendance included Cindy Crawford, Tim Allen, Maria Menounos, a pregnant Molly Sims, Kate Hudson and "Dancing with the Stars" team Val Chmerkovskiy and Janel Parrish.
Special mention must go to Kelly Carlson, who arrived to the party dressed as her own "Nip/Tuck" character, Kimber. Sporting her on-screen alter-ego's trademark haircut, killer cleavage, a black silk robe and plastic surgeon markings all over her body, it was definitely a throwback costume!
Kinda awesome, right?
Check out all of the party pics above -- plus, see more celebrity Halloween costumes from 2014, including Amber Rose's zombie Peg Bundy!
Plus, see some of our favorite costumes of all time below: