Not since Felicity chopped off her curly locks has a television character's haircut inspired so much vitriol.

On Monday night's season premiere of The Big Bang Theory, Penny (Kaley Cuoco) debuted a new pixie haircut. And the show didn't even bother to try to pretend it wasn't a big deal. When Leonard (Johnny Galecki) planned to pick up Sheldon (Jim Parsons) from Arizona, Penny declined to accompany him — because of her new haircut.

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"I don't need six hours of 'Your hair is different. Why did you change your hair? I'm holding my breath until your hair grows back!'" she said.

The haircut is a drastic one. Cuoco scissored her long blonde tresses for a movie this summer. When she posted pics of herself on Instagram, well, people pretty much went nuts.

"That exploded very big. The haircut heard around the planet. We did it three days ago and it got around fast. I can't stop touching it. I am so obsessed with it," she told Women's Health.

While Cuoco had a reason for Pixiegate, it wasn't made clear why Penny made the big chop. Perhaps she was trying to look more mature and professional for her job interviews? Maybe she just wanted a change? Or she may have gotten gum stuck in her hair and had to cut it out?

View photos Stephen Root and Kaley Cuoco More

If Cuoco thought the reaction after her real-life haircut was big, that was nothing compared to what happened Monday night — both on and off-screen. Sheldon did, predictably, react badly. (When he finally returned home, he turned on his heel and left again when he saw Penny's new hair.)

Off-screen, fans were, well, not fans.

To put it mildly, viewers HATED Penny's haircut:

Penny cut her hair? Noooooooooooooooooooooooooooooooo — arturo centurion (@Turkeynole) September 23, 2014

First stop on the fall TV train in our house: catastrophe. Due to Penny's haircut. #bigbangtheory — Deanna Simmons (@deefordisney) September 23, 2014

Penny cut her hair really short, and I hate it on her. I also hate the color. #BigBangTheory — Sarah (@Blondie951) September 23, 2014

Although the new Big Bangs were hysterical tonight, I was very turned off after seeing Penny's new haircut... — Alex Huggins (@wahuggie) September 23, 2014

Why does Penny from #BigBangTheory have the EXACT SAME haircut that I had in 1986? — HeyNiceSweater (@HeyNiceSweater) September 23, 2014

Penny cut her hair on #BigBangTheory. Didn't they learn anything from Felicity? #historyrepeatsitself — Joe Gold (@joetgold) September 23, 2014

The Big Bang Theory airs Mondays at 8 p.m. on CBS.