Emily Ratajkowski, Kim Kardashian, Rihanna and Rita Ora all ramped up the sex appeal as celebrities both sides of the Atlantic battled it out for the sexiest Halloween outfits on Wednesday night.
Leading the pack was US model and actress Emily, 27, who channelled Raquel Welch, 78, for her appearance on Jimmy Kimmel Live wearing a skimpy brown leather dress with huge cut-out details.
In a nod to the classic 1966 film One Million Years B.C., Emily, 27, wore a cleavage-enhancing faux animal skin bikini for the taping.
Royalty: Chrissy Teigen and husband John Legend dressed as Queen Elizabeth and Prince Charles for Halloween
Royal fashion: Chrissy's Queen Elizabeth looked wildly sophisticated in a blue teal overcoat with large black buttons and a matching hat (left) while John cut a regal figure (right)
Kim Kardashian, 37, transformed into starlet Pamela Anderson for her very sexy Halloween costume, after dressing as a Victoria's Secret model.
The reality television star, 38, slipped her curves into a seductive lace corset and fuzzy pink hat to mirror Pam's look at the 1999 MTV Video Music Awards for a Kardashian party.
And Rihanna ensured that even among a host of fellow celebrities in costume that she would stand out on Halloween as she attended the Laylow party in London clad in a figure-hugging latex co-ord.
Heading into the Notting Hill bar, the 30-year-old singer had all eyes on her as she sauntered in alongside the likes of Rita.
Seeing double: Emily looked incredible in her skin-flashing ensemble as she partied the night away, looking uncannily like screen siren Raquel (right)
Blast from the past: Kim Kardashian transformed into Pamela Anderson at the 1999 VMAs for Halloween this year
The Kardashian Angels! All of the Kardashian – Jenner sisters dress up as Victoria Secret Angels for Kim'a Halloween party in Los Angeles. Kourtney, Kim, Kylie, Kendall and Khloe all arrived at Kim's party held in Los Angeles
Singer Rita, 27, also sizzled in a skintight latex trousers that clung to her incredible curves and highlighted her enviably peachy derriere as she channelled Alexandra Medford in The Witches Of Eastwick.
Liam Payne, who has been seen getting cosy with Rita Ora in recent months, decided not to dress up for Halloween, opting for a black coat and printed trousers.
Model of the moment Adwoa Aboah ensured she would turn heads with her Trolls-esque ensemble of a mint green coat and wig, whilst she donned blue body paint and cobalt tights.
Poppy Delevingne donned a floral kimono and teddy to channel Michelle Pfeiffer's Sukie from Witches of Eastwick.
Guess who's here: Liam Payne, who has been seen getting cosy with Rita Ora in recent months, decided not to dress up for Halloween, opting for a black coat and printed trousers
David Furnish rocked a mask and Mick Jagger looked terrifying in a Pennywise the Clown mask, whilst Brooklyn Beckham appeared to be dressed as Oliver Twist in his flat cap and distressed trousers.
Chrissy Teigen, 32, and John Legend, 39, transformed into British royalty, dressed as Queen Elizabeth and Prince Charles.
'Hello Happy Halloween to our loyal subjects,' John said in his best English accent in a video posted on Chrissy's Instagram Story as she slowly walked into the camera shot.
Pretty in prints: Poppy Delevingne donned a floral kimono and teddy to channel Michelle Pfeiffer's Sukie from Witches of Eastwick
And Heidi Klum proved her dressing up box is still brimming with jaw-dropping costume ideas as the supermodel excelled herself at her star-studded bash in New York City on Tuesday night.
The America's Got Talent judge slathered herself in green body-paint and channeled Princess Fiona from hit movie franchise Shrek, with beau Tom Kaulitz dressing as the famous title character ogre
On Halloween morning, she gave a step-by-step glimpse of them undergoing their extensive transformations on Instagram.
'Ok let's do this…. #heidihalloween #heidiklumhalloween #heidihalloween2018,' she captioned a video.
It all started with facial makeup, which led to body prosthetics that made both of them fuller.
The Hallo-queen! Heidi Klum proved her dressing up box is still brimming with jaw-dropping costume ideas as the supermodel excelled herself at her annual Halloween bash in New York City on Tuesday night
In the dark: Heidi chronicled her transformation on her Instagram and shared step-by-step videos
Bella Hadid and the Weeknd dressed as Beetlejuice and Lydia and managed to look uncannily like them
The Weekend -whose real name is Abel Makkonen Tesfaye- wore a scuffed and dirty maroon tuxedo, modeled on that worn by Michael Keaton in the Tim Burton horror comedy.
Meanwhile his supermodel girlfriend dressed as Wynona Ryder's character Lydia- in a bright red wedding dress. She wore a spiked black wig and carried a bouquet of roses.
Meanwhile, Mel B was adding to the hype surrounding The Spice Girls reunion tour as she dressed up as her former bandmate Victoria Beckham, while sporting a mask showing the star in her 2009 image and making a dig with her outfit.
The stunner was joined by a male friend Gary Madatyan, who dressed up as David Beckham while sporting a football jersey and holding a sign saying: 'Please, please, please do it for the Spice Girls fans'.
Kelly Bensimon showed some skin and loads of cash with her costume.
Hilaria, 34, and Alec Baldwin, 60, managed to coordinate all their kids and themselves for Halloween, with all six members of the family dressed in orange astronaut costumes complete with helmets.
Cool cats: Bella Hadid and the Weeknd dressed as Beetlejuice and Lydia and managed to look uncannily like them
Friendly jab: Spice Girl Mel B and boyfriend Gary Madatyan went as Posh and Becks
Double take: Looking identical to the Drag Queen TV star (R), Winnie Harlow showed off her sensational model figure in a skintight lace-up corset which she teamed with thigh-high boots
Wealthy: Kelly Bensimon showed some skin and loads of cash with her costume
Prepare to die: Neil Patrick Harris and David Burtka dressed up as Westley and Inigo Montoya from the film classic The Princess Bride at the bash
Amy Schumer and husband Chris Fischer gave everyone a laugh when they dressed up as Siegfried & Roy.
Newly single Jenna Dewan took Everly, five, to a Halloween party. The actress and dancer, 37, was dressed as Cleopatra for the outing while Everly wore a purple costume as DC Comics superheroine Starfire from Teen Titans.
Nicole Kidman, 51, posted a new photo on Instagram that showed the Oscar-winning actress dressed up as a cat, while Urban, also 51, was decked out as a ninja.
'Halloween fun Xx,' the actress wrote in her caption, along with a ghost and pumpkin emoji.
Family fun! Alec and Hilaria Baldwin joined in on the Halloween fun on Wednesday with their four kids, all dressing up as astronauts in orange outfits
Trick-or-treat: On Wednesday, Amy Schumer and husband Chris Fischer gave everyone a laugh when they dressed up as Siegfried & Roy
Halloween fun: Nicole Kidman and Keith Urban dress up as a cat and a ninja, respectively, to celebrate the Halloween holiday
Party time: Jenna Dewan, 37, was dressed as Cleopatra on Halloween while her daughter Everly, five, wore a purple costume as DC Comics superheroine Starfire from Teen Titans
Granting wishes: Channing Tatum spent his night making wishes come true as he went as the Genie from Aladdin
Stunner: Alessandra Ambrosio showed off her long, lean legs in skin tight red ninja pants and covered her face with a mask
Alessandra Ambrosio, 37, looked stunning in a sexy red ninja costume as she reunited with ex Jamie Mazur to take their two kids trick-or-treating.
Her costume showed off her long, lean legs in skin tight red pants and covered her face with a mask.
Her 37-year-old businessman ex was adorable as he dressed up as Luigi to pair with their son Noah's costume, Mario.
The Super Mario brothers and the ninja were joined by the couple's daughter Anja, 10, and her friend who dressed as the two young girls from The Shining.
Happy Halloween: Robin Thicke and girlfriend April Love Geary (left) made the most of their daughter Mia's first Halloween as they went trick or treating in Malibu, while Ashley Tisdale and her husband also wore matching outfits (right)
Heading out: Bethenny Frankel, 47, sonned an all black outfit with a black wig as she took her daughter Bryn trick-or-treating
Sushi: Hilary Duff, 31, and Matthew Koma, also 31, may have just welcomed a new child, but they still got into the spirit of things as they dressed their daughter Banks up as sushi
Spooky: Reese Witherspoon, 42, dressed as the Corpse Bride, as she joined her family, all wearing spooky costumes
Hilarious: Elizabeth Hurley made sure to flaunt her frame in an unusual Instagram video that saw her channel her inner ninja for Halloween
Justin Timberlake, 37, and Jessica Biel, 36, went all out as they dressed as characters from The Lego Batman Movie with their son Silas.
April Love Geary, 23, and her daughter Mia dressed up as unicorns, while dad Robin Thicke, 41, went as a giraffe.
Ashley Tisdale, 33, and husband Christopher French, 36, both dressed up as sharks as they headed out with their dog in a matching costume.
Hilary Duff, 31, and Matthew Koma, 31, may have just welcomed a new child, but they still got into the spirit of things as they dressed their daughter Banks up as sushi.
Bolts: Kylie Jenner, 21, made a joint costume with her daughter, as they dressed up as Stormi Weather
Kanye: Reign Disick and Saint West went as Lil Pump and Kanye West, respectively, from the I Love It music video
Who wore it better? Saint couldn't wipe the smile from his face as he sported a dark button up shirt over a boxy cut-out with grey trousers with his infamous slipper shoes
Spot on! Taking to Instagram, both sisters Kim and Kourtney shared the adorable shots of their sons dressed as Kanye West and Lil Pump from their music video, I Love It
Bang Bang: Kourtney Kardashian, 39, showed off her dangerous sied in a Ariana Grande costume
Bethenny Frankel, 47, sonned an all black outfit with a black wig as she took her daughter Bryn trick-or-treating.
Reign Disick and Saint West went as Lil Pump and Kanye West, respectively, from the I Love It music video.
Saint couldn't wipe the smile from his face as he sported a dark button up shirt over a boxy cut-out with grey trousers with his infamous slipper shoes.
Reign was also picture perfect with his sweater top and large silver chain, completing the look with unlaced sneakers.
Ali: Olivia Munn, 38, went as a pregnant Ali Wong, going the whole mile with a leopard-print dress
Gorgeous: Elsa Pataky, 42, looked like a hippie princess in a white and gold dress, while Rachel Zoe, 47, was in star pyjama