Michael Kovac/Getty Images for Casamigos Tequila
When Kim Kardashian needed a friend to help her with her Halloween costume, Jonathan Cheban was like, "I got you babe!"
He and the Keeping Up With the Kardashians star dressed up as the late Sonny Bono and pop superstar Cher for the 2017 Casamigos Halloween Party. Kim wore a yellow, long sleeve, bohemian-style crop top and flared pants with sparkling embellishments. Jonathan wore a wig and fake mustache and plum checkered tux. She also sported a long, dark brown wig—similar to her own natural hair—over her platinum blond locks.
The real Cher was very impressed with Kim and Jonathan's tribute.
"@KimKardashian Woke To See You Are Me 4...You Look BEAUTIFUL Little Armenian Sister," she tweeted. "Dream Of India Is Perfect 4U & @BobMackie at his best."
Kim seemed relaxed and in a great mood at the party, E! News has learned. She chatted with model Kelly Sawyer, who was dressed as a cheerleader, as well as other pals. After a few minutes outside, Kim and Cheban linked arms and walked inside the party, did a small lap and left, E! News has learned.
They later had a blast filming Snapchat videos of themselves lip-synching the former couple's 1965 hit "I Got You Babe" and Cher's 1998 dance song "Believe."
The Casamigos Halloween party is an annual bash thrown by the company owned by George Clooney and Rande Gerber. The latter attended Friday's event, which had a '70s disco theme, with wife Cindy CrawfordGeorge's wife Amal Clooney and kids Kaia Gerber and Presley Gerber, who brought friends with them. Amal and the Gerber family wore '70s-style outfits. Amal sported a strapless, sparkling blue jumpsuit, large hoop earrings and round sunglasses and a large, afro-style curly wig.
Amal hung out with Cindy in a booth, had fun dancing to the disco music playlist and drank a Casamigos cocktail.
See photos of famous guests at the party as well as pics of other celebs celebrating Halloween 2017.
The Modern Family star celebrates Halloween week at The Queen Mary's Dark Harbor in Long Beach, California.
"Rapunzel selfie for the win/lose," the actress shared on Instagram while dressed as Disney's Rapunzel.
The Keeping Up With the Kardashians star dresses up like a Powerpuff Girl in her custom Bryan Hearns design.
"Happy Halloween! #copacabana," the "All of Me" singer shared on Instagram while posing with Chrissy Teigen.
Michael Stewart/Getty Images
Ready for Halloween? The Project Runway judge performs Michael Jackson's "Thriller" during her 18th Annual Halloween Party sponsored by SVEDKA Vodka at Magic Hour Rooftop Bar and Lounge at Moxy Times Square.
"Happy Halloween from the crazy people #piratelife," the singer shared with her family.
"Happy Halloween from Woody, Jessie, Ken, Barbie, and BeastMode!" the Teen Mom O.G. star shared on Instagram before trick-or-treating.
Jessica Simpson & Eric Johnson
Hot damn! The husband and wife make quite a splash as Willie Nelson and Waylon Jennings.
Justin Timberlake & Jessica Biel
"If you see us in these streets then have your candy ready! Trick-Or-Treat, little homies!" the pop star wrote on social media, signing the note "Woody, Jesse, and Buzz."
Halsey & G-Eazy
The cute couple enjoy a cuddle during her 2nd Annual Halloween Party presented by Freixenet Cava.
The newly single pop star steps out for trick or treating with her little boy Axl.
Jessica Alba & Cash Warren
The Alba family vants to suck your blood!
Ariel Winter and Levi Meaden
The two dress up as Leeloo and Korben Dallas from The 5th Element.
Emma Roberts & Evan Peters
No American Horror Story here! This couple makes for picture perfect witches.
"Wiz' World," the rapper shared on Instagram before celebrating Halloween at TAO LA and Avenue.
Sarah Michelle Gellar & Freddie Prinze Jr.
"Happy Halloween everyone!" the actor captioned this photo. "Eat your heart out John Cryer! Next year ... Maxwell Houser makes an appearance."
Jessie James Decker
The pregnant country singer and E! reality star holds her very own Mickey Mouse close.
Gisele Bündchen & Tom Brady
Millennials rejoice—the supermodel is the toast to the NFL star's avocado.
Khloe Kardashian & Tristan Thompson
Mother of dragons! The E! reality star and her basketball playing beau go as their favorite characters from Game of Thrones.
Carrie Underwood & Mike Fisher
"The only deer I am OK with @mfisher1212 'catching!'" the country singer captioned the couples shot. "@catchindeers #HelpMe #happyhalloween #veganwifeproblems"
Ryan Lochte & Kayla Rae Reid
It's a whole new world for this Olympic gold medalist and wife who wear costumes from Yandy.com
Kendra Wilkinson-Baskett & Hank Baskett
Trick or treat says this famous family!
Yo ho, yo ho, it's a pirate's life for this actress!
Nate Congleton/NBC News? ?TODAY?
Matt Lauer & Savannah Guthrie
Dolly Parton and Kenny Rogers, is that you?!
Amber Rose & Sebastian Taylor Thomaz
"Chucky ❤️'s Tiffany FOREVER!!!!" the social media sensation shared on Instagram.
Tony Goldwyn, Kerry Washington & Bellamy Young
The cast of Scandal goes all out for Halloween.
Colton Haynes & Jeff Leatham
Cheers! An unrecognizable Colton enjoys some Freixenet Cava while partying with his hubby at Frexienet's 2nd Annual Black Magic Affair.
Rob Kardashian and Blac Chyna's almost 1-year-old tot is a picture perfect Raggedy Ann!
Walk like an Egyptian!
Vanessa & Stella Hudgens
Skeleton sisters! "Nothing better than Halloween decorations, a chai latte, skeleton onesie and mi sister," she captioned this image while wearing PrettyLittleThing skeleton onesies.
David M. Russell, Disney/ABC Home Entertainment and TV Distribution
Kelly Ripa & Ryan Seacrest
It's a Freaky Friday moment courtesy of the talk show hosts!
The Real Housewives of Orange County star works up a sweat at her CUT Fitness studio.
Nate Congleton/NBC News? ?TODAY?
Kathie Lee Gifford, Blake Shelton & Hoda Kotb
The country music superstar surprised the ladies of Today, who rocked coordinating ensembles à la Miley Cyrus and Shelton.
The Good Morning America co-host went as baby Groot from Guardians of the Galaxy.
Alessandra Ambrosio & Jamie Mazur
Marvel's Deadpool and a skeleton walk into a Halloween party...
The actress dubbed her look, "When Spider Witch becomes Spider B*tch at midnight."
The socialite is joined by two of her furry friends for a spooky photo opp.
Neil Patrick Harris
"Hurry, hurry! Step right up and behold the Burtka-Harris Halloween Carnival of Curiosities! #happyhalloween @dbelicious," the actor shared in his family photo.
Stranger Things have happened than this former Playboy bunny dressing up as Eleven from the Netflix series.
"A lego and a bunny go to a party," the Younger star shared on Instagram while posing with her son Luca.
Good Morning America
Super heroes and heroines from the Marvel Universe stole the show at GMA.
The Glee star give a thumbs up at his 8th Annual Halloween Party presented by PAC SUN and Podwall Entertainment at The h.wood Group's Poppy.
The rapper, dressed as Wiz' World, celebrates Halloween at TAO LA and Avenue LA.
Nate Weber / Universal Studios Hollywood
Ariel Winter & Levi Meaden
Traveling in pairs is always better than going solo while at Universal Studios Hollywood's "Halloween Horror Nights."
The supermodel stops the show at with her stunning costume at the 2017 Naked Heart Foundation x amfAR: Fabulous Fund Fair in New York City.
John Sciulli/Getty Images for Chivas Regal
Kristen Doute & Brian Carter
The Vanderpump Rules couple attends Diego Boneta's Halloween Party with Chivas Regal in West Hollywood.
Nicholas Hunt/Getty Images
The model goes Marilyn Monroe for the 2017 Naked Heart Foundation x amfAR: Fabulous Fund Fair in New York City.
"Goals," the Jersey Shore star wrote on Instagram while dressing up one day early with her family.
See More From Stars Celebrate Halloween 2017
Shannen Doherty was spotted with husband Kurt Iswarienko. The actress, who recently battled breast cancer, looked fab in a short black bob wig, fishnet tights, short denim shorts and a black top and was laughing and smiling.
Other celebrity guests included Buffy the Vampire Slayer and Gossip Girl alum Michelle Trachtenberg, Courtney Love, Molly Sims and husband Scott Stuber, Jon Hamm, David Spade, Rachel Zoe, Rachel Roy, Seth MacFarlane, Sacha Baron Cohen (a yellow smiley face emoji) and wife Isla Fisher (a unicorn), Alessandra Ambrosio, Derek Hough (teddy bear) and girlfriend Hayley Erbert (Wonder Woman), Russell Simmonsand Adrien Brody—who dressed up as a panda!