The Odd Detail About Penny That Has Big Bang Theory Fans Talking

Kaley Cuoco played Penny on "The Big Bang Theory" for 12 seasons. During that time, her character became one of the most pivotal parts of the show. Without her, the sitcom's principal group of nerds — Sheldon (Jim Parsons), Raj (Kunal Nayyar), Howard (Simon Helberg), and Leonard (Johnny Galecki) — would probably have remained alone forever. Not only did Penny become Leonard's significant other, but she also introduced Howard to Bernadette (Melissa Rauch) and helped Amy (Mayim Bialik) and Sheldon become a semi-functioning couple. Her importance to the series cannot be overstated.

Fans were introduced to Penny in the pilot of "The Big Bang Theory," when she moved into the apartment across the hall from Leonard and Sheldon's geeky bachelor pad. Naturally, Leonard developed an instant crush on his new neighbor, setting in motion a slow burn romance that captivated viewers for multiple seasons. Still, Penny had nothing in common with Leonard and the rest of the gang early on. Over time, though, she grew close to every single one of them.

Of course, it wasn't always easy for Penny to be around the aforementioned group of socially awkward geeks. Whether she had to put up with Howard's creepy behavior or deal with Sheldon being Sheldon, she spent a substantial portion of the CBS sitcom's 12-season run feeling annoyed. But that only endeared her to fans even more as she had a tendency to display a specific quirk during these moments.

Penny made her anger and frustration known on "The Big Bang Theory." However, while she had no problem speaking her mind, she also wore her feelings on her face. For example, whenever she felt annoyed or things didn't go her way, she made a funny face that saw close her eyes and open her mouth. According to some fans on "The Big Bang Theory" subreddit, this was one of her funniest quirks.

During the discussion, a Redditor by the name of u/Bad_Becky recalled how frequently Penny made this face. "It WAS CONSTANT! Omg," they wrote, suggesting the character was annoyed more often than not. Elsewhere, u/Smapsrof reminded fans "[not to forget] the eye rolls too," while u/DanielKobsted highlighted how she also "[rolled] her tongue on her teeth" afterward.

It's clear that Penny's random quirks haven't gone unnoticed by the show's most eagle-eyed viewers. In fact, they were a major highlight of the series for some viewers. "Penny makes the best facial expressions. I love 'em," u/126-875-358 added. That said, Penny was also known for demonstrating some questionable behavior on occasion, and this detail hasn't escaped some viewers.

There is no denying that Penny's negative reactions to situations provided many laughs for "Big Bang Theory" fans throughout the years. On the flip side, though, some viewers felt uncomfortable with the way she treated people whenever she wasn't happy about something.

A prime example of Penny's more questionable behavior can be found in Season 2's "The Panty Piñata Polarization" episode. Following an incident with Sheldon involving an onion ring, she spent the rest of the episode harassing him, and some fans felt the storyline dismissed the severity of bullying. "I know it's just characters in a stupid show, but I've known people like this and it's like she's picking on the strange kid in school," wrote Redditor u/PhenderMan. "She just keeps egging him on and taking pleasure in it."

In addition to messing with Sheldon, she was prone to belittling Amy and Bernadette, presumably because she felt dumb compared to her friends. However, this type of behavior followed her into marriage too, as evidenced by the way she treated Leonard from time to time. This was especially apparent after he rejected her drunken proposal, which resulted in Penny acting "cruel" toward her significant other, according to some fans.