The last big-time success for a sitcom on a network is arguably The Big Bang Theory, which was a juggernaut on CBS for 12 years. The best thing about the show is how rewatchable it is, with fans easily able to check out any episode they please to follow the exploits of Leonard, Penny, Sheldon, Raj, Howard, Amy, and Bernadette.

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Voters on Ranker have rated which episodes they feel represent the best that The Big Bang Theory has to offer. Since these have hundreds of votes from around the world, there’s no doubt that these stories are the ones that reach the top of the 279 overall episodes in the sitcom.

Season 1, Episode 6: The Middle Earth Paradigm

Penny and Leonard about to kiss in The Big Bang Theory

The first time a truly emotional moment happened in The Big Bang Theory was at the end of this episode. Its premise surrounds the Halloween party Penny invites the guys, where their lack of social skills sees them dress up as geeky characters in contrast to Penny’s guests.

Fans generally like it for the fact that Penny and Leonard had their first kiss. After Leonard stood up for Penny but was embarrassed by her bullying ex-boyfriend, Penny kissed Leonard for his thoughtfulness. Although she was also inebriated, it marked the occasion for the pair to begin their long love story.

Season 6, Episode 4: The Re-Entry Minimization

Penny pins Sheldon to the ground in The Big Bang Theory

It’s always fun watching wholesome moments with the gang and this episode featured quite a few with Leonard, Penny, Amy, and Sheldon. The boys faced off with the girls in various competitions, losing pretty much all of them and garnering some hilarious mocking from Amy and Penny.

The other story is about Howard’s return from space and he doesn’t receive the hero’s welcome he expected when everyone is too preoccupied to care about his presence. The way the two stories connected in the end remains funny and creative, with fans still seeing this as a highly rewatchable episode.

Season 4, Episode 3: The Zazzy Substitution

Sheldon with a bunch of cats in The Big Bang Theory

The first time that Sheldon exhibited his affection for Amy was when he realized he really missed having her around. In this episode, Sheldon’s fight with Amy causes him to look for alternate ways to fill the hole she’s left in her life, leading to Sheldon adopting a clowder of cats.

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Sheldon’s use of the word “zazzy” to describe one of the cats is what makes this episode so memorable, so much so that it’s part of the title. The gang’s numerous attempts to help him get over Amy and the hilarious pratfalls that ensue add to the hilarity of the episode.

Season 3, Episode 22: The Staircase Implementation

Raj, Howard, and Leonard on the couch in The Big Bang Theory

Flashback episodes are something that The Big Bang Theory fans generally love, with this one detailing how Sheldon and Leonard met. Filled with various reveals like how the elevator got destroyed to the signing of Leonard and Sheldon’s roommate agreement, this episode is a real eye-opener.

The kooky appearances of Raj, Leonard, and Howard in contrast to Sheldon appearing the exact same way in the past will always be a source of comedy. At the end of it, fans are also reminded of why Leonard and Sheldon are best friends, as the latter is revealed to have essentially saved his life.

Season 1, Episode 1: Pilot

Penny opening the door in The Big Bang Theory

The episode that started it all remains one of the best in the series for the way everyone’s introduced. Unlike most other shows, The Big Bang Theory’s pilot remains entirely in the comedic territory and never gets sentimental in any way. Here, Penny moved into the building and began her friendship with the guys.

The pilot is a relatively simplistic episode, as it’s mainly about the contrasting attitudes of Penny compared to the rest of the cast. It’s also good to rewatch knowing just how much everyone changes by the end of the series, which goes to show how well The Big Bang Theory handled its storytelling.

Season 3, Episode 18: The Pants Alternative

Drunk Sheldon at a party in The Big Bang Theory

There are quite a few embarrassing moments for the characters in The Big Bang Theory, with this episode bringing one that Sheldon won’t ever live down. The plot surrounds his inability to overcome his stage fright, with everyone else trying different methods to get him out of his shell.

The laughs arrive when each one of the characters fails miserably and all of them end up getting themselves in humiliating situations in return. Of course, the biggest highlight remains Sheldon’s drunken tirade at the end, which is so over-the-top that it’s recorded and goes viral for Sheldon’s embarrassment to remain on the internet forever.

Season 6, Episode 21: The Closure Alternative

Sheldon with a toy in The Big Bang Theory

Another episode that focuses on Sheldon’s quirky habits, this one has Amy forcing him to come to terms with the fact that it’s not possible to gain closure for everything. Amy’s experiments lead to Sheldon being hilariously frustrated with things like not being able to blow all the candles on a birthday cake and to finish the U.S. national anthem.

The subplot of Raj’s attempts to impress Lucy is worth following as well, with Raj trying to act more masculine around her. As expected, Raj ends up creeping Lucy out instead by his out-of-character antics, although the episode has a surprisingly heartwarming reconciliation between the two.

Season 3, Episode 8: The Adhesive Duck Deficiency

Sheldon and Penny at the hospital in The Big Bang Theory

Arguably, the show’s fans love brother-sister moments between Penny and Sheldon more than anything else on The Big Bang Theory. This episode centers around Penny’s injury in the shower that forces Sheldon to care for her, leading to a heartwarming rendition of “Soft Kitty.”

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Even funnier are the exploits of Leonard, Howard, and Raj on their camping trip. The trio accidentally eats questionable cookies which causes them to become delirious. The friends’ admission to embarrassing secrets of their past and zany behavior is the stuff of highlight reels in The Big Bang Theory’s history.

Season 2, Episode 11: The Bath Item Gift Hypothesis

Sheldon hugging Amy in The Big Bang Theory

The ending of this episode brought one of the best friendship moments in The Big Bang Theory when Sheldon willingly hugged Penny. The main premise is about Leonard’s jealousy over handsome physicist David Underhill wooing Penny, while the subplot is about Sheldon searching for the perfect holiday gift for her out of obligation.

Although the overall plotlines are no doubt entertaining, fans largely remember the episode for the bonding moment between Penny and Sheldon. It’s a heartwarming exchange between the two when Sheldon hugs her for giving him a napkin that belongs to Leonard Nimoy and cements their sibling-like dynamic.

Season 3, Episode 20: The Spaghetti Catalyst

Sheldon and Amy having dinner in The Big Bang Theory

Sheldon is kind of like the son Leonard and Penny never had, which this episode takes a spin at. After the pair break up, Sheldon tries to juggle his friendship with both Leonard and Penny and messes things up just as Sheldon can do best.

The show’s fans were appreciative that it took a lighter approach to the fallout from Leonard and Penny’s breakup, with Sheldon presented as the aspect that united the two. It also depicts his inherent loyalty to his friends and fans can never get enough of the times when Sheldon reveals his softer side.

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