Your Favorite Stars Got in the Halloween Spirit With These Fun Costumes

Just like you, celebrities have been plotting, planning, and DIY-ing their Halloween costumes for the past few weeks, so they also couldn't wait until Oct. 31 to show how ready they were for some trick-or-treating fun, kick-starting the spooky celebration a few days early at parties in Los Angeles and New York.

Mario Lopez and his wife decided on a pop culture costume from Saturday Night Fever for their first night out, later going as cowboys with their kids. Alessandra Ambrosio went super sexy as Jessica Rabbit, while Demi Lovato opted for Dorothy from The Wizard of Oz and a maid as her looks. Nicole Richie, once again, stole the show with an elaborate pick, this time as Siegfried and Roy. Read on to see your favorite stars all dressed up, then find a last-minute costume of your own.