There have been very few comedies throughout the history of television that succeeded in the same ways The Big Bang Theory did; it was routinely nominated for the Best Comedy at the Emmy's, with Jim Parsons winning the award for Best Actor in a Comedy four out of five years for his role as Dr. Sheldon Cooper.
Not only was it coveted when it came to awards, but the CBS comedy was a staple for the powerhouse network for more than a decade and remained television's top comedy for several years.
Updated On August 30, 2021, By Lynn Gibbs: After 12 seasons and almost 300 episodes, The Big Bang Theory has more than a few funny episodes. The sitcom has provided fans with endless giggles as Sheldon, Leonard, Penny, and co. go through life as friends and neighbors. The best episodes of The Big Bang Theory often circle around the ensemble as a whole, proving that fans love when this group of friends are together. Over on IMDb, fans have chosen the best episode in every season.
The Stockholm Syndrome, Season 12/Ep.24 (9.6)
The series finale was the highest-rated episode that the show ever had, and for good reason. Amy and Sheldon receive their Nobel Prize awards, with the rest of the friend group watching them from the crowd.
Rather than give a neurotic, self-centered speech about his intellect during the ceremony, Sheldon decides to thank all of his friends for not only putting up with him through the years but also for loving him wholeheartedly. Some fans skip certain Big Bang Theory episodes on their rewatches, but never this one. The final scene has the gang back in their apartment, right where they started, and right where they all belong. It's the emotional ending that gave this episode its high score.
The Bow Tie Asymmetry, Season 11/Ep.24 (9.0)
The season 11 finale saw Sheldon and Amy get married in one of the best episodes. However, the ceremony was delayed slightly due to the fact that Sheldon and Amy come up with their idea of super-asymmetry right before the wedding procession is about to begin. Penny eventually breaks up the science shenanigans, and the lovely genius couple ties the knot.
Fans loved seeing Sheldon and Amy's romance come together so beautifully in this episode. After years of watching them learn and grow from each other, they finally had their happy ending.
The Long Distance Dissonance, Season 10/Ep.24 (8.6)
The third season finale in a row to be the highest-rated episode of the season once again focused on Sheldon and Amy's relationship. When a former colleague who had a crush on Sheldon shows up at the university and eventually kisses Sheldon, all while Amy is away, Sheldon decides to hop on a plane and show up at Amy's front door. When she opens it, Sheldon is on his knee, asking Amy to marry her, and, of course, the season ended with the cliffhanger of Amy not answering.
What made this episode a standout was how determined Sheldon was to get to Amy across the country. He left work, hopped on a plane, and traveled from Los Angeles to New Jersey — all without saying a word. His proposal to Amy made his travels worth it.
The Opening Night Excitation, Season 9/Ep.11 (9.1)
Sheldon and Amy had decided to break up for the first half of season 9 and had only just gotten back together when Sheldon reveals that he wants to have sex with Amy on her birthday.
Meanwhile, the rest of the gang goes to see the opening of Star Wars: The Force Awakens on the exact same night. Both parties are worried that their events won't be all they've built them up to be, but, in the end, everyone winds up having a great time. The big moment of the episode, however, is when Amy and Sheldon finally consummate their relationship.
The Comic Book Store Regeneration, Season 8/Ep.15 (8.1)
The Big Bang Theory might have been a comedy but it certainly dabbled into the emotional territory from time to time, and this was one such episode. The entire premise revolves around different pairings in the gang squabbling over petty and insignificant problems, only for a bombshell to get dropped at the end of the episode revealing that Howard's mother has passed away.
This one was a tear-jerker and one of the saddest Big Bang Theory episodes. However, it stood out in fans' memories as one of the most influential episodes in the series as well.
The Thanksgiving Decoupling, Season 7/Ep.9 (8.9)
Thanksgiving episodes were never a staple for The Big Bang Theory, but the show effectively pulled it off during season 7 when the entire group spends the holiday at Howard and Bernadette's. The day seems to be going fine — that is, until Penny reveals that she got married to her ex-boyfriend Zack in Vegas and didn't realize it was a legitimate marriage. The friends the episode trying to fix the situation, and, of course, they eventually do and everyone gets their turkey.
Seeing everyone watch the drama unfold between Penny, Leonard, and Zack was what really made this standalone episode of The Big Bang Theory's best.
The Bakersfield Expedition, Season 6/Ep.13 (8.4)
The guys were definitely nerdier during the earlier seasons than they were later on, and this episode may take the cake. The men head to Bakersfield for a comic-book convention and decide to stop and have a photoshoot in their costumes along the way.
Unfortunately, their car gets stolen, and they're forced to contemplate whether or not being nerds is worth it. Watching the group go through such highs and lows was entertaining to watch. They ultimately decide that it is when they finally return home and hear their girlfriends arguing over comic books.
The Countdown Reflection, Season 5/Ep.24 (8.6)
The biggest achievement of Howard's life was being sent to the International Space Station, and the season 5 finale dealt with the lead-up to his launch.
This episode is one of the best because Howard and Bernadette decide to get married before Howard goes on his trip — his flight was pushed up — and they have the ceremony on the roof of Leonard, Sheldon, and Penny's building so it can be photographed on Google Earth. The episode ends with Howard's rocket taking off and Howard screaming the whole way up.
The Robotic Manipulation, Season 4/Ep.1 (8.8)
The only season opener that earned the top-rated episode was the one for season 4, which officially introduced audiences to Amy Farrah Fowler — other than a 30-second scene at the end of season 3.
Sheldon and Amy go on a "date" to get to know each other better, and, for some reason, Penny tags along and makes the night even more awkward. Penny's addition to the date is what fans loved the most. Meanwhile, Howard getting his genitals stuck in a robot hand that he invented was also hilarious.
The Staircase Implementation, Season 3/Ep.23 (9.1)
This great Big Bang season 3 episode acted as an origin story of sorts as Leonard recalled for Penny the tale of how he moved into the building and ended up with Sheldon as his roommate. The episode shows how Leonard passed Sheldon's tests for roommateship, how Leonard buys the couch that they still have, how Sheldon and Leonard meet Howard and Raj, and how the elevator breaks — as it turns out, it was Leonard's fault. But seeing how this group came to be all those years before was what makes this episode iconic.
The Bath Item Gift Hypothesis, Season 2/Ep.11 (9.2)
This Christmas episode was one of the best from The Big Bang Theory season 2 and remained the highest-rated episode that the show produced for over a decade, only being bested at the last possible second by the series finale. The episode follows Penny as she falls for a handsome physicist and then deals with Leonard being jealous of the new couple.
Meanwhile, Sheldon feels obligated to get Penny a gift for the holidays and comes up with a solution to give her the perfect present... which fails when Penny ends up giving him an autograph from Leonard Nimoy, and Sheldon has to reciprocate by giving Penny a hug. That one hug from Sheldon was enough to give this episode a whopping score.
The Tangerine Factor, Season 1/Ep.17 (8.6)
It wasn't quite a phenomenon at the time, but The Big Bang Theory was well on its way to being one of television's best comedies when its first season came to a close. The finale follows Penny breaking up with her boyfriend and admitting that she's tired of dating dumb, immature men, to which Leonard responds that he's neither of those things and that the two of them should go on a date.
Penny agrees, but then they both start to have second thoughts and confide in Sheldon, asking him what they should do —Leonard finds this helpful, Penny does not. The episode ends with Leonard kissing Penny to create some chemistry, and then the two head out on their first official date. At this point, this was the start of it all for Leonard and Penny, which is why fans are so attached.