Celebrities go all-out when it comes to costumes ... I mean, that's pretty much their job. I really enjoy it when they dress up as other stars because it adds a funny twist. Here are some good ones from the past few years.
Halsey as Marilyn Manson
Kevin Hart as Dwayne "The Rock" Johnson
Paris Hilton as Miley Cyrus
Miley Cyrus as Lil' Kim
Lisa Rinna as Jennifer Lopez
Chrissy Teigen & John Legend as Queen Elizabeth & Prince Philip
Ciara & Russell Wilson as Beyoncé & Jay-Z
Rita Ora as Post Malone
Sarah Hyland & Wells Adams as Joe Exotic & Carole Baskin
Brie Larson as Britney Spears
Kylie Jenner as Christina Aguilera