Halloween [1] is officially over, but we're still looking back at all the extravagant costumes [2] stars shared in honor of the spooky holiday. On Oct. 29, Robert Downey Jr. [3] got into the holiday spirit early when he let his kids Exton (10) and Avri (7) shave his head in preparation for his upcoming HBO series "The Sympathizer." However, the kids wanted a pretty big favor in exchange for their help — they wanted their dad to become a human jack-o'-lantern. Thankfully, Downey was game, and he chronicled his transformation in an Instagram video captioned, "The things we do for our work… and our kids. #Sympathizer set ready."
Downey isn't the only celebrity who showed off this past Halloween [4]. Hailey Bieber shared a glimpse of her pal Kylie Jenner [5]'s witchy costume from an episode of her "Who's in My Bathroom?" YouTube series [6]. Megan Thee Stallion was also one of the first to get in the spirit, kicking off the month by popping a jack-o'-lantern on her head [7] for a fun at-home photo shoot.
Keep reading to see how more stars, including Kim Kardashian [8], Kourtney Kardashian Barker [9], Megan Fox [10], Dua Lipa [11], JoJo Siwa [12], Vanessa Hudgens [13], Brooklyn and Nicola Peltz Beckham [14], and more dressed up this year.
Heidi Klum as a Worm
Tamron Hall as Ariel From "The Little Mermaid"
Terry Crews as Mr. T and Jennifer Hudson as a Nun
Aubrey Plaza as a Vampire Witch
Rebel Wilson, Ramona Agruma, and Jacob Andreou as Barbie and Ken
Megan Fox and Machine Gun Kelly as Pamela Anderson and Tommy Lee
Liv Lo Golding and Henry Golding as "Top Gun" Pilots
Tyga as E.T.
Taylor Lautner as a Skeleton
Chrishell Stause as a Sexy Skeleton and G Flip as Jack Skellington
Paris Hilton as Sailor Moon
Wiz Khalifa as a Nun
Emma Hernan as "Baywatch" Lifeguard
Ryan Eggold as "The Mandalorian"
Shwayze as a Pirate
Brody Jenner as Anthony Fauci
Kaia Jordan Gerber and Travis Jackson as "Matrix" Characters
Zoey Deutch as the Pink Power Ranger
Juan David Borrero and Jasmine Tookes as Captain Hook and Tinker Bell
Josh Duhamel as Old Man
Sara Sampaio and Zac Frognowski as Targaryens
Cassandra Jean Amell and Stephen Amell as Chuck and Wilson from "Castaway"
Presley Gerber and Lexi Wood as Fred and Wilma Flintstone
Cindy Crawford and Rande Gerber as Cowgirl and Cowboy
Julia Fox as Leeloo from "The Fifth Element"
Jack Whitehall and Roxy Horner
Vanessa Hudgens as a Crow
Prince Michael Jackson as Mario and Blanket Jackson
Paris Jackson as Monster
Jordin Sparks as "Ace Ventura: Pet Detective"
Zuri Hall as Greek Goddess
Elle Kay, Trevor Noah, and Keegan-Michael Key
