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Katy Perry crashes wedding, leaves couple ‘Walking on Air’

ST. LOUIS, Mo. - Surprises are usually the last thing a couple wants on their wedding day, but the unexpected appearance of an uninvited guest at a weekend wedding in downtown St. Louis was a welcome surprise for everyone in attendance.

Four days after their nuptials, Blonie Dudney and Hayley Rosenblum said they're still "Walking on Air.”

“When we were actually getting married, my friends said the sky turned a little purple. It was a really nice backdrop,” Blonie Dudney told KTVI.

Blessed with a beautiful night, this beautiful couple loves each other “Unconditionally," but truth be told, a fairytale wedding wasn’t Hayley’s “teenage dream.”

“Growing up I never really dreamed of getting married. I just wasn’t one of those girls. It really was perfect,” Rosenblum said.

After the servers said, “Bon Appétit,” the Dudneys' guests found themselves “Chained to the Rhythm” on the dance floor. Late in the evening, Hayley learned celebrity appearances aren't just exclusive to "California Girls."

“It was a black-tie event, so when this posse comes in with their baseball hats on, very trendy, it kind of caught my eye. Then she came up to me. Katy Perry came up to me and said, 'Hey, congratulations.' Totally normal,” said Rosenblum.

Like the flash of a “Firework," Hayley says Perry made her pitch.

“She was like, 'We were just at the Janet Jackson concert looking for an after party. We heard the music, do you mind if we crash your wedding?' What am I going to say, no? I was like, 'Of course, come on in.' Then there was a parade of people who came to the dance floor and formed a circle. They were great dancers. I think it was a lot of her backup dancers. It made the party really fun,” Rosenblum said.

The “Roar” of the Dudneys' guests continued as Perry danced and snapped selfies with anyone who asked.

“The nice thing was she really put the attention on Kayley which was great. That was the most important thing.” added Dudney.

Still a blur, like “Waking up in Vegas, it’s pretty clear these now “Legendary Lovers” will never forget last Saturday night.