The Big Bang Theoryis a comedy sitcom, but it includes a few episodes that go beyond just comedy. The CBS show aired in 2007, featuring a group of stereotypically nerdy friends. It gained popularity for its unique comedic style thatdistinguished it from other Chuck Lorre shows, such asTwo and a Half MenandDharma & Greg.

The Big Bang Theoryrelied on various tropes, including stereotypes. It became well-known for the romantic tension between Leonard and Penny, Sheldon’s eccentric behavior, and catchphrase"Bazinga!,“Raj’s extreme shyness, and Howard’s fashion sense and relationship with his mother.

The Big Bang Theory Simon Helberg Howard Wolowitz Nic Cage impression

Over the seasons,The Big Bang Theorybecame extremely popularamong young fans due to its ability to create relatable moments. The show frequently featured pop culture references and real-life problems, such as the episode in which Sheldon had to decide between purchasing a PlayStation and an Xbox.

These instances set the show apart from other comedies, which typically focused on self-contained plots and minimally incorporated real-world occurrences. Additionally, the fact thatThe Big Bang Theoryhad a diverse castof main characters, each distinct in their own way, made it more unpredictable and engaging, and all the more poignant in the moments it dropped the comedic aspect entirely.

Jim Parsons as Sheldon Cooper with Johnny Galecki as Leonard Hofstadter and Bob Newhart as Arthur Jeffries aka Professor Proton in The Big Bang Theory

10Howard Learns His Mother Has Died

Howard & His Friends Grieved His Mother’s Death

Howard’s mother was a notable supporting character who had been part of the show for years. Although she didn’t appear on the screen, she would often be heard yelling at Howard from another room, making her presence felt. In 2014, the actress Carol Ann Susi, who portrayed Howard’s mother, passed away.

The writers decided to honor her by not recasting for her role on the show but instead writing her character off. In the episode,“The Comic Book Store Regeneration,“Howard finally learns about his mother’s death. The show’s tone abruptly shifted from comedy to a more serious and reflective family drama.

Howard Amy and Sheldon stand outside the apartment while Leonard is in the doorway in The Big Bang Theory

9Sheldon Faces Professor Proton’s Death

Sheldon Confronts Mortality In His Own Unique Way

Almost all the characters inThe Big Bang Theoryencountered challenging situations. However, it was particularly memorable to witness Sheldon display a hint of emotion, which added a unique and positive element to the show. In the episode,“The Proton Transmogrification,“Sheldon receives the news of his childhood TV idol, Professor Proton’s death.

The rush of memories, nostalgia, and the realization of the passage of time overwhelm him, leading him to enter a state of denial.Sheldon’s abrupt shift in behavior and the introspectivenature of the episode are highly relatable.

Amy and Sheldon look at one another apprehensively in The Love Spell Potential in The Big Bang Theory

8Amy and Sheldon’s First Night Together

Amy & Sheldon’s Big Step Changed The Show

The episode,“The Opening Night Excitation,“featured an unexpected turn of events. Viewers had long believed that Sheldon wasn’t the romantic type or asexual. However, their perceptions changed when Sheldon made the decision to be intimate with his girlfriend, Amy, for the first time.

Not only did he give her a meaningful birthday gift, but he also chose to forgo his Star Wars night in favor of spending quality time with her. The fact that Sheldon and Amy had a slow-burning romance over the years added a touching element to the episode. It almost felt like a scene from a romantic comedy.

Howard Wolowitz at the International Space Station in The Big Bang Theory

7Sheldon and Amy’s Breakup

Sheldon & Amy’s Split Shook Fans To The Core

The episode,“The Commitment Determination,“aired a few months before the episode in which Sheldon and Amy became intimate. The episode focused on the relationship problems between the couple, with Amy finally telling Sheldon that she needed a break.

It was more emotionally raw than a typicalThe Big Bang Theoryepisode. It ended with a cliffhanger, leaving viewers wondering if it was the end of Sheldon and Amy’s relationship. As viewers now know, things worked out for the two, but at the time, it was heartbreaking to watch.

Kaley Cuoco’s Penny points at Leonard and Raj in The Big Bang Theory pilot

6Howard’s Space Mission Anxiety

Howard’s Pre-Mission Nerves Revealed A Softer Side

Howard was always the fun-loving, awkward guy who often provided comedic relief in most situations. However, the show eventually transformed him into a more serious character, focusing on his personal life and struggles as he pursued his dream of joining NASA. In the episode"The Countdown Reflection,“the show delved into Howard’s upcoming space mission, revealing his acknowledgment of the risks involved.

The episode also highlighted Howard’s relationship with Bernadette, showing the two getting married before the space mission. Overall, the episode felt more like a suspenseful romantic drama than a comedy sitcom.

Kaley Cuoco’s Penny smiles in The Big Bang Theory season 10

5Leonard Confesses To Kissing Another Woman

Leonard’s Confession Hit Penny So Hard

Infidelity is a serious topic that is often portrayed in drama shows or reality TV. Viewers were shocked when they saw Leonard cheat on Penny and eventually confess to her. In the episode “The Matrimonial Momentum,” Leonard and Penny decide to get married in Las Vegas.

However, Leonard’s guilt becomes too much to bear, and he confesses to Penny that he had kissed another woman during a work trip. The decision by the writers to include this storyline in an episode that was supposed to be about the couple’s wedding turned it into more of a serious relationship drama than a comedy show.

Sheldon and Amy’s wedding attires in The Big Bang Theory

4Penny’s Surprise Pregnancy Reveal

Penny’s News Wrapped Up The Big Bang Theory On A High Note

The series finale ofThe Big Bang Theory, titled"The Stockholm Syndrome,“was particularly special. Although the episode was humorous, it also had a heartwarming feel, especially due to the storyline involving Sheldon winning a Nobel Prize.

The most surprising moment occurred at the end, when Penny revealed to her friends that she and Leonard were expecting a baby, making them soon-to-be uncles and aunts. “The Stockholm Syndrome” stood out as an episode that focused heavily on family drama, ultimately making it one of the most memorable season finales of the show.

Kunal Nayyar as Rajesh Koothrappali with Howard’s Stephen Hawking toy in The Big Bang Theory

3Amy and Sheldon’s Wedding

Amy & Sheldon’s Big Day Felt So Satisfying

Wedding episodes are often heartwarming, and that’s exactly what happened in"The Bow Tie Asymmetry,“where Sheldon and Amy tie the knot. The episode focused on Sheldon’s family and friends as he prepares to marry his girlfriend in the presence of the legendary Luke Skywalker and Mark Hamill, the voice of the Joker.

Sheldon and Amy’s wedding was highly anticipated by viewers, and the anticipation, along with the writing, made the episode feel romantic and sentimental. It was a wise choice by the writers not to make it overly humorous.

Simon Helberg as Howard, Johnny Galecki as Leonard, Kaley Cuoco as Penny, Jim Parsons as Sheldon and Kunal Nayyar as Raj in The Big Bang Theory season 5’s intro.

2Raj’s Heartbreaking Love Life Confession

A Rare Emotional Moment For Raj In A Comedy Setting

Raj was another unique character who initially stood out for his behavior. The fact that he wouldn’t speak in front of women made him stand out even more, making it truly intriguing to the viewers. Over the seasons, Raj eventually matured as he gained the confidence to talk to women.

In the episode, “The Bon Voyage Reaction,” he finally confesses his insecurities to his friends, expressing his fear of never finding true love. The character-driven plot of the episode gives viewers a chance to see past Raj’s fun persona, making it feel like a part of a drama show.

1The Series Finale’s Nobel Prize Speech

Sheldon’s Speech Gave Fans A Perfect Goodbye

The series finale,“The Stockholm Syndrome,“deserves another mention on this list. The emotional episode serves as a perfect ending to the long-running series, closing several character arcs. For example, Penny embraces the idea of motherhood by announcing her pregnancy. The most memorable part of the episode was Sheldon’s closing speech, seamlessly shifting from professional to emotional.

Sheldon began by showing off his typical demeanor and gradually opened up about the support from his friends and family, moving everyone with his words. The speech not only provided the episode with emotional closure but also emphasized the personal growth of each member ofThe Big Bang Theory.