Every star of The Big Bang Theory has at least one quote that completely goes against their established personality. The Big Bang Theory’s cast of characters was the show’s biggest strength. By the end of the sitcom’s 12-season run, The Big Bang Theory’s stars were among the highest-paid actors in TV history, and it was easy to see why. The cast balanced absurdity and empathy perfectly, lending heart and humanity to their characters despite how silly and over-the-top they were. However, this doesn’t mean The Big Bang Theory’s characterization was always consistent, as evidenced by various notable quotes.
By The Big Bang Theory’s finale, the main characters of the series were almost unrecognizable from their pilot incarnations. Howard went from a sleazy pickup artist to a loving husband and devoted father, while Raj outgrew his inability to speak to women and ended up going through numerous serious romantic relationships. Leonard gained confidence and charisma via his relationship with Penny, while Penny embraced her intelligence and her nerdy side thanks to her partner. Sheldon learned humility, while Amy went from a female version of Sheldon to a more distinct, and distinctly bizarre, character of her own.
10. “Please don’t hurt my friend” — Sheldon
Season 6, Episode 2, “The Decoupling Fluctuation”
Sheldon’s humanity shone through as The Big Bang Theory explored his character more, but one of his most unguarded moments was uncharacteristically plainspoken and humble. In season 6, episode 2, “The Decoupling Fluctuation,” Sheldon stressed how much Penny and Leonard’s potential breakup would impact his life. This concern seemed typically self-centered, as did Sheldon’s insistence on litigating the breakup with Penny in the middle of the night as she attempted to sleep. However, Sheldon’s plea for Penny not to break Leonard’s heart was atypically sympathetic and genuine as the arrogant, self-obsessed character prioritized his friend for a change.
Sheldon had many moments of unexpected generosity over the years, but these usually came about via his unusual priorities. Sheldon didn’t value money, so he thought little of lending Penny a lot of cash. However, in “The Decoupling Fluctuation,” Sheldon’s sincere heart-to-heart came from a place of true humility, and this was a side of the character that rarely resurfaced even in later seasons. One of The Big Bang Theory’s worst wasted Penny plots saw Sheldon rudely refuse acting lessons from his friend, and it’s hard to believe that the same character once selflessly plead Leonard’s case to her.
9. “Come on, scientist to scientist, how big are those hadron colliders?” — Amy
Season 8, Episode 5, “The Focus Attenuation”
When she was first introduced, the basic premise of Amy’s character was that she was a female version of Sheldon. Sheldon’s friends thought it would be amusing to set him up on a date, the dating site’s algorithm worked too well, and they accidentally made their persnickety friend more powerful by introducing him to his female counterpart. However, this wore thin over time and, gradually, Amy’s character changed. Season 8, episode 5, “The Focus Attenuation,” was one of the most notable early instances of this shift when Amy pushily asked about Bernadette’s bra size, something Sheldon would never have done.
8. “You and I have both grown a lot, and it’s just so nice to see you all again” — Leslie Winkle
Season 9, Episode 17, “The Celebration Experimentation”
In The Big Bang Theory’s early seasons, Sara Gilbert’s Leslie Winkle was the sardonic scientist who kept the gang in check with her withering put-downs. Leslie could even silence Sheldon despite his outspoken arrogance, so it was a shock when she was polite and cordial with the gang in season 9, episode 17, “The Celebration Experimentation.” Since The Big Bang Theory’s underused Leslie hadn’t been seen for multiple seasons at that stage, it briefly seemed as if she had changed completely. However, she instantly reverted to her sharp-tongued old self when Sheldon admitted that he preferred her rude, abrasive personality.
7. “You’ve broken up with me so many times, which first date are we talking about?” — Leonard
Season 7, Episode 6, “The Romance Resonance”
Leonard harbored a lot of resentment towards Penny over their perceived differences, often fearing that he wasn’t good enough for her. However, he rarely voiced these, as he was usually busy trying to impress her or stay on her good side. As such, it was a surprise, and not an entirely welcome one, when Leonard bitterly pointed out the couple’s numerous breakups in one season 6 outing. Leonard’s toxic side wasn’t always on display, but it was pretty unmistakable when Penny pointed out that the duo didn’t celebrate their first date and Leonard questioned which one she meant considering their breakups.
6. “I’ve been babysitting him way longer than you have.“ — Raj
Season 10, Episode 6, “The Fatal Kick Catalyst”
Raj was a constant presence in Howard and Bernadette’s relationship, despite how much strain this put on the pair. As if to make up for this imposition, Raj rarely got into direct conflict with the infamously fiery Bernadette. Howard’s wife begrudgingly accepted his presence in their lives but was unlikely to welcome Raj’s attempts to undermine their relationship. As such, it was out of character for Raj to cattily inform Bernadette that he had been babysitting Howard for longer than her in season 10, episode 6, “The Fatal Kick Catalyst.” That said, he wasn’t wrong given Howard and Raj’s closeness in earlier seasons.
5. “Yeah, doing the prom queen’s homework so she’ll like us.” — Bernadette
Season 6, Episode 6, “The Extract Obliteration”
While Howard and Bernadette’s Big Bang Theory relationship proved Bernadette was a tough, unapologetic woman who refused to be mistreated, her friendship with Penny was more complicated. Throughout most of The Big Bang Theory, Bernadette had no problem standing up to Penny. Whether she was telling her which projects to accept at work or informing her and Amy that she would be the one to dress as Cinderella, Bernadette was outspoken and unafraid of Penny’s threats. As such, it was jarring and out-of-character when she, alongside the more accommodating Amy, meekly acquiesced to writing Penny’s papers for her.
4. “You look like Tigger if Tigger looked like a jackass.” — Stuart
Season 9, Episode 23, “The Line Substitution Solution”
Stuart’s character changed a lot throughout The Big Bang Theory, primarily because his function in the series was also altered during this time. Early on, Stuart was contrasted against the show’s gang. He was confident and charismatic despite his geeky interests and seemed to fare fine romantically. As the series continued and the love lives of Howard, Leonard, Sheldon, and even Raj improved, Stuart became a tragic figure of fun whose deteriorating life was inherently comical. However, he remained polite and friendly. Thus, his vicious put-down of Raj, which was admittedly paid for by Howard, was wildly out of character.
3. “That’d be mighty white of you.” — Mary
Season 5, Episode 6, “The Rhinitis Revelation”
As some of Young Sheldon’s best quotes prove, Mary Cooper was not always the demure church mouse she aspired to be. However, she also wasn’t cruel or thoughtless, despite her small-minded tendencies, and her intense religious faith didn’t always make her an outright bigoted figure. That said, season 5, episode 6, “The Rhinitis Revelation,” saw Mary use the outdated term “Mighty white” to refer to something kind and charitable. Ironically, Mary said this after Leonard offered to write her a list of outdated, problematic terms to avoid. However, this cluelessness was too extreme to ring true for the well-meaning character.
2. “Well, he thinks I’ve seen every one of the Star Wars movies, but I’ve really only seen the one with the gold robot.” — Penny
Season 12, Episode 7, “The Grant Allocation Derivation”
Penny was a free-spirited party girl when The Big Bang Theory began, so it seems reasonable that she wouldn’t be overly familiar with even the most mainstream of nerdy interests. However, she spent the series growing increasingly invested in nerd culture, eventually reading comics out of interest, quoting Star Trek and Star Wars, and proving adept at Halo and Fortnite. Penny became obsessed with an online roleplaying game and was talented at chess, proving that she has plenty of interest in traditionally nerdy hobbies and activities. As such, the revelation that she had only seen a single Star Wars movie felt out of character.
Penny had displayed an understanding of Leonard’s nerdy Star Wars jokes and quoted the movies herself.
In season 12, episode 7, “The Grant Allocation Derivation,” Penny admitted she had only seen a lone Star Wars movie while speaking to Bernadette about white lies. This set up a fun punchline about C-3PO, but beggared belief given what viewers know about her character. The Star Wars movies have made over $10 billion at the box office and this scene took place in the show’s final season, after Penny had displayed an understanding of Leonard’s nerdy Star Wars jokes and even quoted the movies herself. Thus, this revelation didn’t quite fit Kaley Cuoco’s Big Bang Theory character.
1. “Yeah, I would not have done that for you.” — Howard
Season 10, Episode 1, “The Conjugal Conjecture”
Howard and Raj were incredibly close in The Big Bang Theory’s first few seasons and, although Howard prioritized his wife and children in later outings, the pair still shared one of the show’s most enduring friendships. As such, it felt out of character when Howard blithely admitted that he didn’t care about Raj as much as Raj cared about him. In season 10, episode 1, “The Conjugal Conjecture,” Raj lied to the government to protect Howard, then pointed out just how risky this decision was after the fact. Rather than thanking him or acknowledging this sacrifice, Howard made a thoughtless joke.
Howard saying that he didn’t care about Raj as much as Raj cared about him didn’t ring true.
Howard’s claim that he would never have shown Raj the same kindness felt wrong, since the character sacrificed plenty for his friend over the years. Admittedly, both Raj and Howard occasionally double-crossed each other, especially when potential romantic entanglements were involved. However, the pair almost always had each other’s backs, so Howard saying that he didn’t care about Raj as much as Raj cared about him didn’t ring true. Howard undoubtedly had plenty of character flaws, but The Big Bang Theory character wouldn’t have let his friend down even if it meant going above and beyond (or, more specifically, lying to the government).
