Sexy, Scary, Sweet: Stars pull out all the stops to celebrate Halloween in style

Rihanna, KarJenners, Emily Ratajkowski and Rihanna turn up the heat with some seriously sexy Halloween outfits

                            Sexy, Scary, Sweet: Stars pull out all the stops to celebrate Halloween in style

The Queen of Halloween Heidi Klum never fails to impress

Heidi Klum in her show-stopping look as Princess Fiona at her 19th Annual Halloween Party in New York on October 31. Klum's boyfriend Tom Kaulitz accompanied her as Shrek. (Photo by Noam Galai/Getty Images for Heidi Klum)

Emily Ratajkowski's sexy cavewoman costume set pulses racing

Emily Ratajkowski channeled Raquel Welch from the 1966 film 'One Million Years BC' at Travis Scott's Halloween bash in Los Angeles. (Photo by Vivien Killilea/Getty Images for Deliliah)

Rihanna looks spookalicious in sexy skeleton outfit!

Rihanna went for a scary yet sexy look wearing pink skull face makeup along with a black patent leather bustier and tights as well as spiky heels at Rita Ora‘s party in London. (Photo by GORC/GC Images)

Sophie Turner and Joe Jonas clearly have an eye for detail

Joe Jonas and Sophie Tuner looked sensational as they dressed as Gomez and Morticia Addams from The Addams Family. (Instagram)

Rita Ora flaunts serious cleavage in see-through outfit

Donning a slinky black and purple semi-sheer dress, 27-year-old Rita Ora appeared to be channeling Cher's character Alexandra from the 1987 film 'The Witches Of Eastwick' at her party in London. (Instagram)

Kourtney Kardashian is perfection as Ariana Grande

Kourtney Kardashian dressed up as Ariana Grande to take her kiddos trick or treating. Kourtney sported a pink babydoll dress and thigh-high boots, carrying a microphone and wearing a large ponytail wig with silver rings braided into the roots. (Instagram)

'Life in Plastic, It’s Fantastic,' says 'self-made' billionaire Kylie

Kylie Jenner completely transformed into a real-life Barbie doll for Instagram. Kylie is packaged and secured with plastic wiring into a Barbie doll box, wearing a one-shoulder pink bodysuit teamed with statement necklace, a big bouncy blond wig and shiny plastic-like skin. (Instagram)

This insanely cute mother-daughter duo is melting hearts

Khloe Kardashian and Baby True dressed as matching unicorns in cute pink outfits and won over Instagram (Instagram)

Bella Hadid and The Weeknd are back and happier than ever

Bella Hadid and The Weeknd dressed as Beetlejuice and Lydia from the 1988 classic 'Beetlejuice' for Heidi Klum's annual Halloween party in New York City. (Photo by Jackson Lee/GC Images)

Neil Patrick Harris and David Burka honored a comedy classic

Neil Patrick Harris and David Burtka dressed up as Westley and Inigo Montoya from 'The Princess Bride' for Heidi Klum's 19th Annual Halloween Party in New York City. (Photo by Taylor Hill/FilmMagic)

Lupita arrived as one of the most badass ladies of the 90s

Lupita Nyong'o dressed up in the character of Dionne from 1995's 'Clueless' for Heidi Klum's 19th Annual Halloween Party in New York City. She looked incredible in her black and white patterned ensemble which included a red top above her white tee shirt. (Photo by Taylor Hill/FilmMagic)

At 44, supermodel Kate Moss can give youngsters a run for their money

Kate Moss transformed into a vampire for Rita Ora's bash in London, wearing an all-black outfit and long black wig. Her face was painted white, with red lips and eyes. (Instagram)

The Rolling Stones frontman was unrecognisable as Pennywise

Mick Jagger dressed up as Pennywise from the film 'It' for Rita Ora's Halloween bash in London. (Photo by Mark R. Milan/GC Images)

TV's most famous family outdid themselves as they turned heads by the dozen

In one of the many looks they adopted for Halloween, the KarJenners — Kourtney, Kim, Khloe, Kylie and Kendall — borrowed former runway looks from lingerie giant Victoria's Secret for coordinated costumes... and the angels looked dreamy and gorgeous as they strutted through Los Angeles (Instagram)

Kim Kardashian flaunts her newly acquired tiny waist

Kim Kardashian oozed glamour in a cream lingerie set that showed off her impressively toned abs and famed hourglass curves (Instagram)