Singer Ariana Grande teased fans for days with black and white clips from the 1960s American television show The Twilight Zone before unveiling her impressive costume from its infamous "Eye of the Beholder" episode.
Basketballer LeBron James nailed it as his very own "LeDward Scissorhands".
Television host Ellen DeGeneres also knocked it out of the park as a racy Cardi B – or "Cardi E" as she joked.
Jessica Biel rocked up to a Beverly Hills Halloween party dressed as her husband Justin Timberlake during his NSYNC days, while Timberlake dressed as a microphone.
"This is what happens when you admit on TV that you don't know any NSYNC songs and you're married to Justin Timberlake. Well played, husband, well played," Biel wrote on Instagram.
Nicki Minaj was a hallo-queen as DC's manic villain, Harley Quinn.
Kate Beckinsale looked positively darling in a Holly Golightly costume from Breakfast at Tiffany's, while friend Jonathan Voluck channelled Elton John in the film, Rocketman.
Australian comedian Em Rusciano went all out as Disney's terrifying sea witch Ursula from The Little Mermaid, while fellow comedian Joel Creasey hosted an event at the Forum Theatre in Melbourne as a zombie usher.
Kevin Hart trolled his Jumanji co-star Dwayne 'The Rock' Johnson by recreating his famous fanny pack photo from 1994.
Bring It On star Gabrielle Union-Wade gave us all the feels in her iconic Clovers cheerleading costume from the 2000 film.
Supermodel Cindy Crawford was a psychedelic disco diva at her husband Rande Gerber's Casamigos party.
And Elizabeth Hurley wowed as The Bride, played by Uma Thurman in the revenge thriller, Kill Bill.
Halloween queen Heidi Klum will unveil her outfit at a bash on Friday but has posted a series of terrifying teaser clips on Instagram.
In Australia, The Project host Carrie Bickmore and her family dressed as a "motley crew" including Elsa from Frozen and a pumpkin.
Meanwhile, Home and Away star Ada Nicodemou channeled the day of the dead with her family.
