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Karlie Kloss as a Sexy Cat and Joan Smalls as Minnie Mouse
If you're looking to coordinate with your BFF, the supermodels' cat-and-mouse costumes (at the The Metropolitan Museum of Art's 2017 "All Hallows' Eve" benefit) are all the stylish inspiration you need.
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Lauren Conrad as Cruella de Vil
As usual, Conrad revealed her 2017 costume early, and Disney fans will love it: The star is rocking two-tone hair, a faux fur coat, LBD, long red gloves and a bold red lip to channel 101 Dalmations' Cruella de Vil. The cutest part? The new mom revealed on her website that she's dressing up three-month-old son Liam as a tiny dalmation.
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Sara Foster as Melania Trump and Erin Foster as Ivana Trump
Will the real First Lady please stand up? The Foster sisters capitalized on the drama between Donald Trump's ex-wife Ivana (who boldly claimed "I'm first lady" in an interview on Good Morning America) and current wife Melania by posing as the pair in a cleverly timed partnership with Svedka Vodka.
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Beyoncé, Jay-Z and Blue Ivy as Barbie and Ken
The whole family was in on the costume in 2016, with Bey as "Black Barbie," Jay as her Ken and Blue in a painted moto jacket, tights and light-up shoes.
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Keke Palmer as Selena Quintanilla
We can only imagine Palmer said "It's a bustier!" several times throughout the evening.
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Zoë Kravitz as Princess Peach
The actress took on the role as video-game royalty alongside her Mario (boyfriend Karl Glusman) and artist Trouble Andrew a.k.a. "GucciGhost."
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Khloé Kardashian as Storm
She may have dressed like one of the X-Men for the night, but with that body, we're not entirely convinced Kardashian herself isn't a superhero.
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Chanel Iman as a Mummy
The model looked dead-chic in her mini and over-the-knee boots, wouldn't you say?
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Cindy Crawford and Presley, Kaia and Rande Gerber as a Punk Group
The family that rocks together, stays together.
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JENNIFER LOPEZ AS A COUTURE SKELETON
Leave it to J.Lo to take a classic Halloween costume and turn it into something totally new (and totally contoured).
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KENDALL JENNER AS KARL LAGERFELD
Considering Kendall is one of Kaiser Karl's muses, it's no surprise she paid homage to the designer with a (somehow sexy?) costume — complete with a friend dressed as his famously spoiled cat, Choupette.
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FERGIE AND JOSH DUHAMEL AS KARL LAGERFELD AND CHOUPETTE
Sorry Kendall, you weren't the only one with this idea! Josh and Fergie also dressed as the designer and his fashionable feline.
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ALLISON WILLIAMS AS BELLE
Belle's yellow dress may be the more iconic Beauty in the Beast look, but Allison went with her more academic (and slightly more subway-appropriate) blue apron look.
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NICKI MINAJ AS A 'FAIRY F---ING PRINCESS'
Nicki is rap royalty, after all, so why not dress the part?
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JESSICA ALBA AND KELLY SAWYER AS ROMY AND MICHELE
Let's just say they invented Post-its.
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SERENA WILLIAMS AS A PROM QUEEN
The tennis star went full-'80s as a geeky — but still victorious — prom queen.
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POPPY DELEVINGNE AS HARLEY QUINN
The model (and Cara's sister) channeled Margot Robbie's badass Suicide Squad character, down to her signature accessory: a baseball bat.
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LAUREN CONRAD & FRIENDS AS 'PARTY ANIMALS'
Lucky us: Conrad has already revealed her costume for 2015! The DIY enthusiast and her squad are going as very chic “party animals,” a.k.a. the perfect excuse to wear both a formal gown and bunny ears. Add a glass of champagne (keep 'em coming) and you're good to go!
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BEYONCÉ AS JANET JACKSON & BLUE IVY AS MICHAEL JACKSON
Bey, we're gonna let you finish in your Rhythm Nation-inspired ensemble, but Blue Ivy has the best Michael Jackson costume OF ALL TIME!
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TAYLOR SWIFT AS A 'PEGACORN'
Think she has a matching crop-top outfit on under there? Swift skipped her signature night-out style to dress as a whimsical unicorn-Pegasus hybrid in 2014.
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HEIDI KLUM AS A BUTTERFLY
Klum is the reigning queen of Halloween, and her epic butterfly costume from 2014 didn't disappoint. Now the question is, how will she top herself this year?
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LAUREN CONRAD AS A MERMAID
Ariel has nothing on Lauren Conrad and her handmade(!) mermaid dress. If you're feeling ambitious, the full how-to is on Conrad's blog, but you can also do the lazy girl's version and pair a sequined skirt with a tropical-print top. And don't forget a flower for your hair!
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LAUREN CONRAD AS THE TOOTH FAIRY
Yes, LC's in here three times – the girl gives good costume! Her tooth fairy look from 2013 was also a DIY creation, and her now-husband William Tell adorably dressed as a dentist to coordinate.
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KIM KARDASHIAN WEST AS ANNA WINTOUR
Not only did Kim pay homage to the Vogue editor in chief in 2014, but she dressed up little North as Wintour's right-hand man, Andre Leon Talley. And if that wasn't cute enough, her makeup artist Joyce Bonelli and her son joined in as Grace Coddington and tiny Karl Lagerfeld, respectively.
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KENDALL JENNER AND CARA DELEVINGNE AS MARIO AND LUIGI
These two stylish besties are basically inseparable, so we weren't surprised to see them pair up for Halloween in 2014. What we weren't expecting was for them to go as video-game brothers Mario and Luigi – although Kendall does pull off that moustache better than we would have thought.
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KATE MOSS AS CARA DELEVINGNE
Some people say Cara is the new Kate, but if Moss' spot-on costume is any indication, we may have it all backwards.
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MILEY CYRUS AS LIL' KIM
Lil' Kim's purple pasty is one of the most shocking VMAs fashion moments of all time, and Miley is a die-hard fan of pasties, so this was a match made in Halloween heaven.
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EMMA ROBERTS AS VIVIAN FROM PRETTY WOMAN
We've seen a few Pretty Woman costumes in our day, but no one can hold a jewelry box full of diamonds up to Emma Roberts' – a.k.a. Julia's niece! – back in 2012.
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JESSICA SIMPSON AND ERIC JOHNSON
These two may have gone the simple route in 2014 by simply wearing masks, but who cares? They looked hot! And in a move that is both innovative and a little creepy, Johnson's mask is actually Hanky Panky underwear, according to Simpson's Instagram.
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JOE JONAS AS DEREK ZOOLANDER
Jonas' costume in 2014 was so on-point, it's as if Mugatu himself designed it. And now that Zoolander 2 is officially underway, we wouldn't be surprised if we see a few more Blue Steels than usual this year.
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RITA ORA AS BARBIE
The singer went full Barbie girl for a 2014 Halloween party in London, pairing her sexy pink dress with a matching crown and various life-size accessories.
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LEA MICHELE AS LITTLE RED RIDING HOOD
My, what high heels you have! Little Red Riding Hood got a sexy makeover, courtesy of the Scream Queens star's 2014 costume.
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SARAH HYLAND AS EDIE SEDGWICK
Hyland rocked a mod '60s look – and a blonde pixie cut! – to channel Andy Warhol muse Edie Sedgwick in 2014.
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RACHEL ZOE AS THE EVIL QUEEN FROM SNOW WHITE
Zoe, here with her Huntsman-slash-husband Rodger Berman, dared to go wicked in 2014. Sorry Snow White – capes are just so much more major.
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LINDSAY ELLINGSON AS SANDY FROM GREASE
Tell us about it, stud. The Victoria's Secret model slipped into Sandy's skintight pants for Heidi Klum's 2013 bash.
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BRAD GORESKI AS TAVI GEVINSON
Before Gevinson became a bona fide editor and actress, she was just your average 13-year-old fashion blogger with purple hair. Goreski perfectly captured the teen's kooky-old-lady look at a Lanvin-hosted party in 2010, down to her signature thick-rimmed glasses.