Last night (June 14) on the reality competition TV show America's Got Talent, 10-year-old contestant Harper stunned the judges and the audience by brutalizing them with a cover of Spiritbox's breakout song "Holy Roller."

You may recognize the youngster from the vocal cover video she released last year, which perfectly showcased her capabilities as a seriously talented metal screamer. All that practice paid off as Harper found herself onstage on the hit NBC show where reactions shifted from YouTube comments to the opinions of the trio of America's Got Talent Judges — Heidi Klum, Sofia Vergara and Simon Cowell.

Just before her moment in the spotlight began, the judges invite Harper's father, who was standing on the wing of the stage, to join them behind the booth to watch his daughter make her mark on not only the panel and the live audience, but everyone else watching at home as well.

Harper's performance initially stirs confusion amongst Klum, Vergara and Cowell after the spoken word refrain "Holy roller sits in the garden we fled / blood into wine, take my body instead," but the Somerset, U.K. native quickly erases this notion with a series of ferocious growls and higher pitched shrieks.

Host Terry Crews can't believe what's happening onstage and looks directly into the camera, wide-eyed and flashing the devil horns hands gesture.

"I love it. I'm so proud," says Harper's dad after Cowell asks what he thinks of it all after his daughter's turn onstage had ended.

As extreme vocals become more commonplace in music and in reality TV contests, the reactions are typically one of surprise but there now seems to be a fairly high level of respect for this vocal technique amongst the judge's panel.

"Have you ever seen a film called The Exorcist? Actually, kidding aside, that was brilliant. I mean, brilliant. It was like a mouse turning into a vampire bat or something," comments Cowell, to which Vergara adds, "And it was so effortless. Her face was not transforming into a monster. It was something come out of her that was so crazy."

With three "yes" votes from the judges, Harper secured her spot in the next round, meaning more brutality could be in store for millions of at-home viewers.

Watch the full performance clip below. Loudwire wishes you good luck in the next round, Harper!

And, as if life couldn't get better, Harper hit the stage with Spiritbox in London on the very same night the America's Got Talent episode aired, as seen in the photos she shared on Twitter directly below.

America's Got Talent Contestant 10-Year-Old Harper Screams Spiritbox's "Holy Roller" (video title incorrectly states Harper is 9)

25 Rockers Who've Been on Reality TV Shows

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