Lady Gaga Worked With a Vocal Coach Every Day for 6 Months for Epic 'Sound of Music' Performance

But one person not impressed? Shonda Rhimes.

Hard work really does pay off.

Lady Gaga stunned even her haters (well, almost all of them, but we'll get to that later) with her The Sound of Music tribute on Sunday night's Oscars. While better known for pop songs like "Poker Face" and wearing crazy outrageous costumes, she sounded sounding amazing performing a medley of the classic tunes including "My Favorite Things," "Edelweiss" and "Climb Ev'ry Mountain" in a gorgeous gown fit for a princess.

But the flawless vocals weren't exactly effortless -- Oscars executive
producers Neil Meron and Craig Zadan revealed to ET that the 28-year-old
singer actually practiced every day for six months for the 50th
anniversary tribute.

"She worked half a year with a vocal coach every day for half a year to do that," Zadan told ET.

"She's the real deal," Meron added. "She can do anything."

VIDEO: Lady Gaga Slayed Her 50th Anniversary Oscars Tribute to 'The Sound of Music'

Meron also revealed just how seriously the "Applause" singer took the performance.

"She said that if she pulls it off, it's going to change the focus of her career and she pulled it off," he said.

"I'm just very excited to be here and I really put my heart into this performance," Gaga herself told ET on the Oscars red carpet. "It's a tribute performance for a remarkable film that changed the history of cinema forever, and I'm just very honored to be doing it."

But though Gaga's been getting rave reviews for her surprising performance, one person clearly not impressed is Scandal showrunner Shonda Rhimes.

Rhimes tweeted about Gaga's performance on Sunday, and let's just say the review is far from glowing.

Haters gonna hate? And really, it's just one negative review in a stream of countless rave reviews.

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Relive Gaga's show-stopping performance in the video below.

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