Gemma and Bobby, who are in Vegas with their TOWIE co-stars to film a two-part special, planned to see the renowned R&B group in a hotel on the Strip last night (23 September).
But after getting dolled up to the nines for the show, the BFFs were left gutted when they turned up and realised the band weren't performing after all!
During the afternoon, both Gemma and Bobby had even headed to The Wynn hotel's beauty salon to ensure they were looking their best for the Boyz.
Sharing a picture of himself, Bobby tweeted: "Lovely visit to the @WynnLasVegas salon.. Cheeky eyebrow shape for tonight! Hope @BoyzIIMen appreciate my efforts..."
He then uploaded a photo of Gemma midway through a pampering appointment, adding: "Now it's @missgemcollins turn to get dolled up for the @BoyzIIMen show tonight! #BigBouncyBlowdry."
Once they were ready, Bobby tweeted another snap, commenting: "Me and @missgemcollins love a selfie.. Now off to see @BoyzIIMen."
Sadly though, their evening with Nathan Morris, Wanya Morris and Shawn Stockman wasn't to be.
Within an hour, Bobby had told his followers: "So me and @missgemcollins get to the venue to find out @BoyzIIMen aren't even playing!! #fail." Oops!
They shouldn't feel too sad though, as Gemma and Bobby did get to meet 'Elvis'....
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