Talk about being left with egg on your face!
To make matters worse the assailant was a past contestant on the talent show, Natalie Holt, who was playing with the orchestra, before breaking away and running front and center on stage.
Holt made her move during a performance by opera singers Richard and Adam Johnson on the season finale of the show, and managed to fire off a few eggs before being dragged from the stage by security.
Proving the show must go on, Richard and Adam carried on singing throughout the attack, not missing a note!
"I want to apologize to Richard and Adam for overshadowing their performance," Holt said after the show. "I've never done anything like this before and in hindsight I have realized it was a silly thing to do."
Meanwhile, TV's Mr. Mean appeared to take it all in his stride.
"I really don't like eggs," he tweeted.
"Bloody hell! Just watched the Adam and Richard performance back. They didn't miss a note," Cowell added later.
Unfortunately for the Johnson brothers though that wasn't enough to snag the coveted top place, they were placed third.
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