And the garments weren't from Rylan Clark’s eccentric outfit collection.
Nope, the boys of Union J instead decided to borrow some clothes from Ella Henderson’s collection.
Perhaps they were trying to help her feel more comfortable after being the only female act on the tour.
Pretty boy Josh stepped out of his comfort zone donning a glittery blue top and gold skirt owned by Ella as Union J took to the stage to perform their last ever song.
The band uploaded a photo of the transformation onto their official Twitter account.
They captioned the shot: “This is how we dressed for the final song on tour tonight!!! Hahahaha!!! Yes...., josh is wearing Ella's outfit! Heels and all! G x”
George Shelley also got in on the dressing up action, wearing a rather fetching pair of gold parachute pants and leather Adidas jacket.
Suffice to say, the boys looked ridiculous.
Still, dressing up as a woman never did David Walliams any harm- he landed himself Lara Stone after all- so we doubt the picture harmed Josh’s popularity with the ladies too much.
Union J confirmed earlier this year that they were working on their first single, due for release in May, after signing to Sony.
The boys will also be performing alongside the likes of Olly Murs, Stooshe and X Factor winner James Arthur at a Alton Towers live gig on July 6.
The band excitedly tweeted earlier today: “Can't wait for Alton Towers Live 6 July, Tickets on sale now!”
We wonder if Josh will be back in his normal clothes by then...
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