
Although The Big Bang Theory ended back in 2019, these ten episodes of the series are still seen as masterpieces by fans online. With its laugh track, close-knit group of thirty-something leads, multi-camera setup, and frequent romantic subplots, in many ways, The Big Bang Theory was a fairly conventional hang-out show.
While The Big Bang Theory’s upcoming spinoff, Stuart Fails to Save the Universe, has an ambitiously meta sci-fi premise, the original show was mostly concerned with the low-stakes antics of its central friend group. What made the show stand out from the formula established by Friends, How I Met Your Mother, Happy Endings, New Girl, and Seinfeld was its main characters.
The Big Bang Theory followed a quartet of nerdy friends and their glamorous neighbor, with two new love interests joining the regular cast in seasons 3 and 4. Unlike most earlier hang-out shows, The Big Bang Theory reveled in the unabashed nerdiness of the gang’s interests. However, as a rundown of the show’s strongest episodes proves, this wasn’t all that made the series work.
From a season 2 standout to The Big Bang Theory’s series finale, the episodes of the show that stood head and shoulders above the rest worked because they twisted its usual formula. Instead of simply pairing up Leonard and Penny, Howard and Bernadette, Sheldon and Amy, and Raj and his latest paramour, these outings found fresh perspectives on familiar friends.
10“The Intimacy Acceleration”
Season 8 Episode 16
Penny and Sheldon’s love experiment proves that the pair are closer than they think, resulting in a lot of big laughs before a moving ending that doubles down on the episode’s emotional impact.
However, this is not all that stands out about the episode. Penny and Sheldon’s love experiment proves that the pair are closer than they think, resulting in a lot of big laughs before a moving ending that doubles down on the episode’s emotional impact.
From start to finish, both the A-story and B-story of “The Intimacy Acceleration” are atypically emotional for The Big Bang Theory. This sort of episode can be a big swing for a show whose sense of humor tends toward the cynical, but the end result is a well-earned moment of pathos in a series that is typically far more glib.
9“The Staircase Implementation”
Season 3, Episode 22
The Big Bang Theory | ||
---|---|---|
First Ever Episode | Pilot | Sept 24, 2007 |
Final Episodes | The Change Constant (Finale Part 1) | May 16, 2019 |
The Stockholm Syndrome (Finale Part 2) | May 16, 2019 | |
Total Seasons | 12 | 2007 – 2019 |
Spin-Off Series | Young Sheldon | 2017 – 2024 |
Georgie & Mandy’s First Marriage | 2024 – |
Is it mostly an excuse to dress them up like late ‘80s geeks even though the episode takes place in the late ‘90s? Yes, but this only makes “The Staircase Implementation” even funnier, and proves to be a fun way to illustrate how much Sheldon has grown throughout the show.
While The Big Bang Theory’s Leonard and Penny were its original focus, episodes like this highlighted just how much Jim Parsons’ scene-stealing earned the spotlight. By the show’s ending, Sheldon would be its protagonist, and the change wasn’t unwelcome thanks to his fascinating character.
8“The Focus Attenuation”
Season 8 Episode 5
Meanwhile, Amy and Bernadette let loose in Las Vegas, but Penny surprises everyone by hanging back to take her job a little more seriously. While The Big Bang Theory finale’s Penny story wasn’t entirely satisfying, this episode proves just how much Penny’s character subtly changed and gradually grew throughout the show’s story.
7“The Opening Night Excitation”
Season 9 Episode 11
What makes “The Opening Night Excitation” so special is its careful balance of two interlinked storylines. Amy’s excitement and nerves about losing her virginity to Sheldon are contrasted with Leonard, Howard, and Raj’s excitement and nerves over a new Star Wars movie, and the result is an episode steeped in geek culture that maintains a deeply human edge.
The Big Bang Theory is available to stream on Hulu.
6“The Adhesive Duck Deficiency”
Season 3, Episode 8
As Young Sheldon’s best secret cameo proves, Sheldon and Penny’s relationship was arguably The Big Bang Theory’s most important overarching story. Sheldon taught Penny patience while Penny taught him to be more understanding, and both became more accepting thanks to their fire-forged friendship. “The Adhesive Duck Deficiency” is a particularly great instance of this friendship in action.
Sheldon’s sincerely well-meaning but comically clumsy attempts to help Penny highlight both his flaws and his innate, if well-disguised, decency.
Everything about “The Adhesive Duck Deficiency” is perfectly judged, from Sheldon’s ineptitude at helping an injured, showering Penny to the rest of the gang’s meteor-spotting camping trip. Sheldon’s refusal to attend an outdoor event is perfectly in character, while his sincerely well-meaning but comically clumsy attempts to help Penny highlight both his flaws and his innate, if well-disguised, decency.
5“The Lunar Excitation”
Season 3, Episode 23
While Stuart Fails to Save the Universe promises to change the entire world of The Big Bang Theory, the show itself did this more than once. Amy’s arrival in The Big Bang Theory’s season 3 finale fundamentally altered the course of the series, forcing Sheldon to avoid character stagnancy by giving him the last thing viewers expected. Namely, a romantic partner.

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In time, Amy also became a lovable character in her own right, but what makes “The Lunar Excitation” a masterpiece is its killer setup. After Raj and Howard set Sheldon up with his female counterpart as a prank, they soon realize to their horror that they may have just made their friend far more powerful by accident.
4“The Scavenger Vortex”
Season 7, Episode 3
This scavenger hunt proves that there are myriad secret sides to the main characters that viewers barely even glimpsed throughout the series.
In the years since, Georgie & Mandy’s First Marriage proved that even the show’s smallest supporting stars could support entire shows of their own. This revelation wouldn’t surprise viewers who saw Bernadette’s ultra-competitive side come out in this scavenger hunt, proving that there are myriad secret sides to the main characters that viewers barely even glimpsed throughout the series.
3“The Bath Gift Item Hypothesis”
Season 2, Episode 11
Although “The Bath Gift Item Hypothesis” arrived only halfway through the show’s first season, this Christmas special highlighted the potential of The Big Bang Theory early on. Later, a more explicitly ambitious Christmas special would explore a version of the show without Sheldon, but this early episode was a straightforward story of yuletide joy.

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Although the B-story of “The Bath Gift Item Hypothesis” is equally strong, it is Penny and Sheldon’s adorable story that makes this one a masterpiece. Not only that, but its Yuletide setting makes an annual rematch a necessity.
2“The Stockholm Syndrome”
Season 12, Episode 24
Although Sheldon’s character development in The Big Bang Theory’s finale was somewhat undone by the ending of Young Sheldon, the last episode still deserves a spot on this list. Sheldon’s Nobel Prize acceptance speech is a poignant reminder of the considerable growth his character has undergone throughout the show, and the rest of the gang receive their requisite happy endings too.
As Vulture’s Kathryn VonArendonk noted at the time, Penny’s pregnancy does feel sudden and not entirely justified, while Raj’s continuing singledom is an unfortunate reminder of how much he was sidelined in later seasons. However, even these issues prove that “The Stockholm Syndrome” doesn’t try to hide the show’s shortcomings in its final outing.
Where many sitcoms will try to paper over earlier failures with a schmaltzy, sentimental ending, The Big Bang Theory’s finale is as messy, imperfect, and enjoyable as the preceding twelve seasons. As such, it more than earns a place on this list.
1“The Celebration Experimentation”
Season 9, Episode 17
As noted above, the true story of The Big Bang Theory only emerged over time. Sheldon became the show’s main character as viewers singled him out as the ensemble’s standout, and his troubled friendship with Penny became thornier, more complex, and more interesting than either of their respective romantic relationships.
The Big Bang Theory Franchise Project | Release Years | # of Seasons |
---|---|---|
The Big Bang Theory | 2007-2019 | 12 |
Young Sheldon | 2017-2024 | 7 |
Georgie & Mandy’s First Marriage | 2024-Present | 1 |
Stuart Fails To Save The Universe | N/A | N/A |
Penny’s shameful acknowledgment that she would have bullied Sheldon in school is a fitting rejoinder to the many criticisms of Sheldon’s treatment of Penny, and Sheldon’s sincere thanks to his friend for helping him regain his composure are unexpectedly moving. The scene is a standout that proves The Big Bang Theory truly understood its characters, for all the show’s shortcomings.
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