Kat Dennings & Andrew W.K.
The 2 Broke Girls alum and her rocker husband partied hard as a cat and a wizard, respectively.
Halle Bailey & Chloe Bailey
Jinkies and jeepers! The sisters were the perfect mystery solvers as Daphne and Velma from Scooby Doo.
Elizabeth Gillies
The former Nickelodeon star looked unrecognizable as the titular villain in Longlegs.
Camila Cabello
In girl world, the "Havana" singer paid tribute to Mean Girls by wearing Regina George's Halloween costume.
Irina Shayk & Bradley Cooper
The friendly exes dressed as Lara Croft and a wolf, respectively, to take their daughter Lea trick-or-treating.
Gwen Stefani
There was no doubt the "Hollaback Girl" singer was going all out for Halloween, dressing up as Snow White to throw a party.
Josh Gad
The Frozen actor's Abby Lee Miller costume earned him a spot at the top of the pyramid.
Nelly & Ashanti
The "Body on Me" couple embraced the wild west at a Western-themed Halloween party that also celebrated Nelly's 50th birthday.
Natalia Bryant
Kobe Bryant and Vanessa Bryant's daughter channeled Cher's Burlesque character.
Emily Ratajkowski
The model gave a nod to Jennifer Lopez with a plunging green gown similar to the singer's iconic Versace dress.
Amelia Dimoldenberg
The Chicken Shop Date host was always watching as Roz from Monsters Inc.
Michaela Jaé Rodriguez
Sul sul! The Pose alum recreated Bella Goth's iconic look from The Sims video game franchise.
Frankie Muniz
The Malcolm in the Middle alum had an arresting Halloween costume opposite of his son Mauz.
Sabrina Carpenter
The "Espresso" singer was working late dressed as a Playboy Bunny.
Sabrina Carpenter
She also underwent Olivia Newton-John's classic Grease makeover.
Patrick Mahomes & Brittany Mahomes
The Kansas City Chiefs quarterback and his pregnant wife roared into Halloween by dressing as zoo animals with their two kids Sterling and Bronze.
Colton Underwood
The Bachelor Nation star and his son Bishop dressed as Linguini and Remy from Ratatouille.
G-Eazy
Accio, Harry Potter! Or as the rapper (born Gerald Gillum) put it on Instagram, "Gerry Potter."
Chase Stokes & Kelsea Ballerini
The couple—dressed as Danny and Sandy from Grease—had themselves a blast at Heidi Klum's Halloween party.
Sexyy Red
The "Get It Sexyy" rapper, dressed as a nun, took fans to church during her debut performance at E11EVEN Miami.
Kendall Jenner & Kylie Jenner
This is what dreams are made of! The Kardashians stars recreated the iconic looks of Hilary Duff's Lizzie McGuire and Isabella Parigi characters from The Lizzie McGuire Movie.
Matthew McConaughey & Camila McConaughey
Raise a glass to the couple dressed as bottles of their Pantalones Organic Tequila.
Winnie Harlow
The model came out and let it show in her Diana Ross costume.
Saweetie
Why so serious? The "My Type" rapper—dressed as Joker from The Dark Knight—would like to know.