For round two on Halloween, Jenner and her girlfriends go as a gang of ninjas, complete with faux weapons, sexy outfits and serious hair extensions.
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This is Halloween for the starlet, who gets all dolled up as The Nightmare Before Christmas lead Jack.
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Seriously, where is Waldo? There are so many of them! The actor (second from left) and his pals have us seeing stripes during the Oct. 31 Trick or Treats! magazine party at LIGHT Nightclub at the Mandalay Bay Hotel in Las Vegas.
It took Klum nearly 10 hours to go from bare-faced to barely recognizable for her Saturday fete sponsored by Svedka and GSN's Hellevator at N.Y.C.'s Lavo, for which she dressed as Jessica Rabbit. All that's missing? Roger, of course!
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What did Lopez, with beau Casper Smart at Klum's Svedka- and GSN's Hellevator-sponsored party, go as this Halloween? A "haute couture skeleton," she writes.
It's hard not to laugh at the reality star's costume: herself.
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Is that a white swan and black swan we spy?
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CHANNING & JENNA DEWAN TATUM
The husband and wife go as The Cat in the Hat – two ways! – for the starry Casamigos Tequila bash in L.A.
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Also at the Casamigos bash: The Voice mentor, who of course makes a classic look extra-cool.
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The Dancing with the Stars judge takes a cue from her "favorite movie," True Romance, and goes as Alabama (with a friend dressed as Clarence).
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It's not easy to figure out exactly what Jenner and her friends are dressed as, but she makes it easy for us: "Babes."
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MOLLY SIMS & SCOTT STUBER
The model mama is hot as a sexy tiger, while her husband is even hotter as Jurassic World's Chris Pratt.
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"@kellysawyer n I invented post-its," Alba jokes of the friends' Romy and Michele's High School Reunion-inspired disguises.
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We'll admit we don't know what the former reality star and her pal are dressed as, but it sure is scary.
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Of course the regal mogul arrives via horse and carriage to his Oct. 31 Ciroc party at Marquee in New York City.
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As The Biebs knows, dressing as a Will Ferrell character (in this case, Jackie Moon from Semi-Pro) is never a bad idea.
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"Ugh Belle I've been telling you to get a damn Kindle," the Girls star jokes.
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We can really appreciate a costume that's both cute and cozy.
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JOSH DUHAMEL & ARIANA GRANDE
"It was an udder pleasure @arianagrande," Duhamel cracks of the pair's Friday run-in.
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DARREN CRISS & NOLAN GERARD FUNK
Halloween getups or just a Thursday night out? Doesn't seem to matter for Glee's Criss and Funk, who get dressed up and dramatic.
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POPPY DELEVINGNE & CAMILLA AL FAYED
At the UNICEF UK Halloween Ball on Thursday, Delevingne channels Suicide Squad's Harley Quinn as her pal pulls off a pretty believable Medusa.
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Our best guess for this bloodied pair: a post-shoot-out Bonnie and Clyde.
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Grant is the mane event on Thursday at the UNICEF Halloween Ball in London.
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Meanwhile, Sheen steps right up as a ringmaster.
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Hey there Little Red Riding Hood! The supermodel goes sexy in Santa Monica, California, on Halloween eve.
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Hey, what's up? Hello ... she's a "Trap Queen," get it? The pop singer dresses as summer's pop hit – complete with crown, sash and mini bear-traps – for an early Halloween celebration in N.Y.C.
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Whoa, Mama! The expectant star goes all-out with facial hair and a spiked wig for her take on Food Network star Guy Fieri, bravely showing the world that even a supermodel looks questionable in a flame-adorned button-up shirt.
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KELLY RIPA & MICHAEL STRAHAN
Is it hot in here, or is it just the Live! with Kelly and Michael hosts teasing their Halloween costumes? The stars pose alongside producer Michael Gelman and head of production Art Moore on Tuesday in Magic Mike-inspired stripper wear. Strahan appeared in the sequel Magic Mike XXL, but Ripa blends in with the veteran just fine with the help of a generous amount of fake chest hair.
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You poor unfortunate souls will never be able to craft a costume to top Colton Haynes'. The Arrow actor uses vine, body paint and a fierce white wig to dress up as Ursula from The Little Mermaid for Matthew Morrison's annual Halloween party in L.A.
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It's the best group costume of all time: the Spice Girls. TVD's Dobrev and her friends transform into Baby, Posh, Scary, Sporty and Ginger for the night at Morrison's Halloween party, sponsored by Dos Equis.
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Now these are the superheroes our world needs. At Ciara's birthday party, the whole gang dresses up as their favorite caped crusaders – including a ice-blue-eyed Beyoncé as Storm from X-Men.
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GOLNESA "GG" GHARACHEDAGHI
The Shahs of Sunset star goes for a twist on a classic costume – a cat – at Maxim's Halloween party in L.A., donning a skin-tight leather bodysuit. Meow.
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VAL & MAKS CHMERKOVSKIY
They're used to being in costume on Dancing with the Stars, so is it any surprise that the Chmerkovskiy brothers do it big on Halloween? Val is an unidentified suited man, and Maks is Prince Charming for the Maxim bash.
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We know where Jonas got his post-party eats! He dresses up as the classic McDonald's "villain," the Hamburglar, at the Karma International and Maxim party.
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CHRISTINA MILIAN & ANNALYNNE MCCORD
Milian goes full feline at Carlton's Halloween Nightmare! in L.A. in a leopard-print bodysuit and cat ears, while 90210 alum McCord sticks to a spooky look with a sheer black robe and face paint.
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JOHN STAMOS & JOSH PECK
It's co-star costume time! Grandfathered actors Stamos and Peck break out the face paint for their matching costumes – as devils – at Carlton's Halloween Nightmare!
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ROBERT DOWNEY JR.
He may be out of the Iron Man suit, but RDJ is just as fierce as a striped tiger as he is as Tony Stark's alter ego in this Insta pic.