Kim Kardashian was left red-faced after arriving at a birthday bash in full Halloween fancy dress before realising that it wasn't a costume party.
The reality TV star, 42, was painted blue as she dressed up as Mystique from X-Men as she arrived at actress pal Tracee Ellis Ross' 50th birthday event.
She wore a full latex costume, complete with the slicked back red hair as she channelled the character for a photoshoot earlier that day.
The SKIMS founder joined friend Olivia Pierson, 33, as Magik, and Natalie Halcro, 34, as Selene, for an X-Men themed shoot ahead of Halloween.
Kim then headed straight for Tracee's bash, an event she seemingly thought she'd fit right in while wearing her out-there costume.
But it would seem she stuck out like a sore thumb as the other guests appeared to be wearing posh gowns and smart attire.
Taking to Instagram to highlight her embarrassment, Kim posted: "That time I showed up to a birthday dinner in full costume when it wasn't a costume party!"
"Happy Birthday to the most beautiful soul @traceeelliseross," she added – attaching a snap of the pair inside a fancy restaurant – Kim in her blue X-Men outfit and Tracee wearing a classy red gown.
It is thought Kim went straight to a Halloween party to make use of her fantastic get-up, joining rapper Diddy who was dressed as the Joker.
"Never broke character," Kim praised the musician on social media as she shared a selfie with the I'll Be Missing You chart-topper.
Diddy also took to his Instagram later in the night to post a picture of his outfit in full – tagging Kim as she can be seen stood in the background.
It comes after mum-of-four Kim divided fans after sharing what her kids were wearing for Halloween.
North, 9, Saint, 6, Chicago, 4, and Psalm, 3, were dressed in 'icon' attire as they transformed into Aaliyah, Snoop Dogg, Sade Adu and Eazy-E.
It was over on Twitter that fans slammed the outfits, with some suggesting that the kids' wanted to be something different for Halloween.
"Uhm… they’re children Kim. Are you sure they don’t wanna dress up like minions or something? Just saying lol," one fan asked.
Speaking of Saint's Snoop Dog attire, another fan said: "That baby on the right wanted to be spider man. You played Kim." A third said: "He looking like I wanted to be Spider-Man."
"They wanted to be Fortnite characters kimberly," suggested a fourth.
However, another praised the outfits, saying: "Omgggg. Too iconic and amazing not to post."
Others have compared Saint's Snoop Dog outfit so his dad Kanye West, saying that he is a 'spitting image' of the Bound 2 rapper.
One Twitter follower said: "Chi is literal perfection and Saint should’ve just dressed up as Ye cuz that’s exactly who he looking like lol."
"Saint's got his daddy's eyes for SHORE," tweeted another.
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