The Big Bang Theory: The 5 Best (& 5 Worst) Episodes

In its historic 12-season run, CBS' The Big Bang Theory has produced nearly 300 episodes. We take a look at the best and worst of them.

As hard as it may be to believe, the little show about a group of nerdy friends and their adventures through life has become the longest-running multi-camera sitcom of all time. More than that, the beloved CBS series The Big Bang Theory will soon be wrapping its incredibly successful, lengthy twelve-season run, capping off at nearly 280 episodes when all is said and done.

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The Big Bang Theory began as a cult hit series that focused on the nerd subculture, lovingly paying tribute and parodying it in equal measure. Somehow, almost overnight, the series skyrocketed to become one of the most-watched series on television. With nearly 300 episodes under its belt before the series wraps, The Big Bang Theory has had some truly timeless classic episodes, but there have been some real stinkers mixed in too.

10 Best: "The Romance Resonance"

The Romance Resonance episode of The Big Bang Theory

The Big Bang Theory is almost always at its best when it focuses on the relationships between its core group. When it adds an extra emotional punch that nobody sees coming, it's even better. Episode Six of the series' seventh season, entitled "The Romance Resonance," does all of that and more. The main plot of the episode consists of Howard's plans for a romantic evening and celebration of the anniversary of his first date with his wife, Bernadette.

When a chemical accident at Bernadette's work results in her being forced into isolation, the entire night seems like it's going to be a bust - until Howard and the gang show up and serenade her with a truly touching song. While most of the song consists of Howard detailing how he wouldn't be complete without Bernadette, the general emotional thrust of the song finds the entire gang observing that they "couldn't have imagined how good our lives would get from the moment that we met you, Bernadette."

9 Worst: "The Imitation Perturbation"

The Imitation Perturbation episode of The Big Bang Theory

As we just discussed, The Big Bang Theory is often at its best when it focuses on the moments of real, meaningful connection within the core group of guys and girls. For that reason, episodes that feature tension and petty fighting among any pair of characters usually stand out as some of the series' weakest. Arguably the weakest of them all was the series' final attempt at Halloween episode, the twelfth season's "The Imitation Perturbation."

Howard dresses up as Sheldon for Halloween, mocking his style of dress and mannerisms. When Sheldon is rightfully hurt by this, what follows is a war of wills and words between married couples Sheldon and Amy and Howard and Bernadette. The episode's central conflict isn't flattering for any parties involved, and the show could've done without it altogether.

8 Best: "The Work Song Nanocluster"

The Work Song Nanocluster episode of The Big Bang Theory

One of the hidden gems (and secret weapons) of the entire series has unarguably been the relationship between scientific genius Dr. Sheldon Cooper and well-meaning airhead Penny. While the series sadly lost track of their friendship in later seasons, earlier seasons featured many episodes that detailed their unlikely adventures and the advancement of their friendship. One of the best such episodes was the Season Two entry "The Work Song Nanocluster."

After Penny starts an online business selling hair clips called Penny Blossoms, Sheldon gets roped into helping her mass produce orders for her online store. An absolutely hilarious adventure featuring sea shanties, far too much caffeine, and Sheldon in a Flash costume follows, securing the episode a spot on the list of the best of the best.

7 "Worst: The Relationship Diremption"

The Relationship Diremption episode of The Big Bang Theory

Sometimes, you just have to sit and wonder how a specific storyline made it out of the writers' room and into production. The seventh season episode "The Relationship Diremption" features one of those very sort of plots. The series has always struggled when it comes to Raj's romantic life, and his relationship during that arc (with the too eccentric Emily) was undoubtedly one of the worst attempts at finding him a significant other.

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Even before this episode's unsavory revelations, Raj and Emily were a poor fit for each other. It became even more obvious that there was no future to this relationship when it was revealed that Howard and Emily had once gone on a blind date (which ended abruptly after Howard destroyed her bathroom due to some stomach issues then snuck out as fast as he could).

6 Best: "The Scavenger Vortex"

The Scavenger Vortex episode of The Big Bang Theory

Adventures that feature the entire gang are usually a guaranteed hit in the series' catalogue. But these adventures are even better when they find characters pairing off into unconventional combinations. "The Scavenger Vortex," the third episode of the series' seventh season, finds the friendship group tasked with a scavenger hunt put together by resident creative party thrower, Raj.

During the scavenger hunt, the group breaks off into three pairs: Leonard is paired with the fiercely competitive Bernadette and Sheldon and Penny get to resume some of their always-hilarious banter, while Howard and Amy find unlikely common ground as they bond over their mutual love of the music of Neil Diamond. The twist at the end of the episode only makes everything all the more hilarious, ensuring that future viewings will be even more enjoyable.

5 Worst: "The First Pitch Insufficiency"

The First Pitch Insufficiency episode of The Big Bang Theory

The Big Bang Theory is, and has always been, a show about nerds. It does what it does best when it's celebrating nerds, not looking down on them in any way. Unfortunately, as the series progressed, episodes where nerds were the butt of the joke became all too frequent. Howard is one of the most frequent targets of this mockery - for reasons including the fact that he's the only member of the friendship circle without a PhD.

Even his work with NASA leads to humiliation on multiple occasions, such as the eighth season episode "The First Pitch Insufficiency." After he realizes he'll never be able to throw out the first pitch at an Angels game as NASA requested, engineer Howard sets about building a robot that will do it for him - only for the robot to fail, embarrassing him more than a lousy pitch ever would.

4 Best: "The Convention Conundrum"

James Earl Jones in The Big Bang Theory

Other episodes of The Big Bang Theory celebrate what it means to be a nerd, and praise the lives of nerds in all their many forms. One of the most notable examples of these celebratory episodes is the seventh season episode "The Convention Conundrum." Dissatisfied with the schedule and offerings of that year's San Diego Comic Con, Sheldon sets out to form his own comic fan convention. Of course, nothing goes as planned.

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The result is one of the most absurd adventures the series has ever chronicled. Sheldon quickly hits it off with Darth Vader himself, James Earl Jones, and the duo spend the day together. They're seen pranking Carrie Fisher, eating ice cream, riding a Ferris wheel, relaxing in a steam sauna, and singing "The Lion Sleeps Tonight" at karaoke. It's something straight out of every nerd's dream - but it was so very, very real.

3 Worst: "The Skywalker Incursion"

The Skywalker Incursion episode of The Big Bang Theory

Yet another episode that mocks nerds more than it ever celebrates them is the misguided eighth season episode "The Skywalker Incursion." While half of the episode is mostly harmless, chronicling Sheldon and Leonard's attempts to visit Skywalker Ranch, the episode's other main plot is in incredibly poor taste.

While cleaning out the Wolowitz garage, Bernadette and Howard engage in a fight about his nerdy memorabilia and how much of it he can keep. At the heart of the conflict is a replica of the Doctor Who TARDIS, something which is incredibly important to Howard. The solution proposed? A ping pong tournament, to see who can decide what happens with the collector's item. Bernadette is portrayed as even crueler than usual during the episode, making it all the more difficult to endure.

2 Best: "The Bath Item Gift Hypothesis"

The Bath Item Gift Hypothesis episode of The Big Bang Theory

Sheldon Cooper has never been gifted at reading social cues or following social protocols. It's what makes the second season Christmas episode "The Bath Item Gift Hypothesis" so immediately charming from the very beginning, as he frets over what sort of gift to get for his frenemy and neighbor, Penny. Leonard and Sheldon's related debates about the Christmas holiday and Saturnalia also provide the episode with some of the series' strongest nerd credential material.

It's the episode's final act that seals its status as among the best of the best. Penny, then a waitress at the Cheesecake Factory, surprises Sheldon with a one-of-a-kind gift: a napkin autographed by Leonard Nimoy. Sheldon, in turn, is more thrilled about the prospect of possessing Nimoy's DNA than anything else. What follows is the moment that makes the episode so absolutely great: in his sheer delight, Sheldon becomes like a child, throwing countless gift baskets at Penny and - to her utter shock and glee - embracing her in a hug.

1 Worst: "The Matrimonial Momentum"

Leonard and Penny's wedding was a long time coming for the series. Their coupling had been foreshadowed from the very first episode, and they were taken on a back and forth, will they, won't they rollercoaster throughout the show's run. As such, when the duo decided to get married in a spur of the moment Vegas wedding in the ninth season premiere "The Matrimonial Momentum," it felt... unsatisfactory. A total let-down for all the build up they'd been given.

Making matters worse, however, was the eleventh hour reveal that Leonard had once cheated on Penny. It ruined what should have been a special moment, and a significant episode for the series. The couple would get to re-enact their wedding later in the season, but the bad taste lingered all the same.

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