Mumford & Sons were playing Phoenix last week when they were forced to get creative when their opening act, Gang of Youths, had to canceled due to illness.

Prior to the show, the band posted a cryptic message to Twitter with the caption “Huge night tonight fellas. First ever gig. Possibly the last. Lots of pressure but feeling great. Get down early if you’re here.”

Who the hell are The Sun Never Sets on the Cool Kids? Well, they’re Mumford & Sons in costume! Little did the audience know that they’d be treated to a series of covers from the band before their show would begin.

Frontman Marcus dressed up as a glam rocker while other bandmates dressed up as Fred Flintstone, a T-Rex, a police officer, the Pope and other fabulous looks.

The band performed six covers before taking the stage in their natural form.

“You Shook Me All Night Long” (AC/DC cover)
“You Really Got Me” (The Kinks cover)
“Wagon Wheel” (Old Crow Medicine Show cover)
“The Weight” (The Band cover)
“Girls Just Wanna Have Fun” (Cyndi Lauper cover)
“Atlantic City” (Bruce Springsteen cover)