In the first episode of the Big Bang Theory, Leonard and Sheldon meet a woman moving into the apartment across the hall. While she introduces herself as Penny, nothing seems strange about this at first—most people don't say their full name when introducing themselves. However, what was strange was that over the 12 seasons of the show, the audience never learned her surname! Sure, her surname would eventually become Hofstadter, but that isn't the closure fans wanted.
The creators of the show suggested that the reason for this was that there were such high expectations around her last name that they could only disappoint fans if it were revealed. The creators took the easy way out and decided to keep it all a mystery.
For Amy and Sheldon, receiving a Nobel Prize would be like completing a long and difficult video game. They have achieved the highest pinnacle in their career, where do they go from there? It would seem odd for two characters who love their careers as much as Amy and Sheldon to move on to a different subject, but perhaps they could. Both characters have interests outside of academia that they could pursue.
When the audience was first introduced to Raj, he was unable to speak to women unless he was drunk. However, as the overall series progressed Raj finally overcame this barrier in his life and was then able to speak to women while sober.
Even though he is now able to speak to women, he still hasn't managed to find love. This is despite the fact that the rest of the group, including Stuart, having managed to find relationships. This begs the question, then: will Raj ever find a girlfriend?
No one ever really expected Sheldon to be in a relationship, yet, by season 12, he was married to Amy Farrah-Fowler. One question that was unanswered in season 12, however, was whether or not Amy and Sheldon will have kids. The two have already gotten married, so it would seem like children would be the next step in their relationship.
While Young Sheldon has suggested that Sheldon will become a father someday, it still isn't as satisfying as a reveal on the actual show would have been. Seeing Sheldon as a father would certainly be a sight to behold!
Throughout the series, Howard is the butt of several jokes due to the fact that he has never received a Ph.D. Howard did consider completing a Ph.D. during the series, but never ended up actually completing the degree. Perhaps, after his children have grown, he will go back and complete a Ph.D.
While Howard is already a successful engineer and is under no obligation to get a Ph.D., he does not enjoy being on the end of Sheldon's jokes, but will he receive a doctorate to put an end to Sheldon's barbs?
If you showed a random person the first and last episodes of the Big Bang Theory, apart from likeness, Sheldon would be unrecognizable. Throughout the seasons, Sheldon slowly became more sociable and self-aware. Sheldon even developed a very close relationship with Penny.
Not only did Sheldon go on to get married, but he also learned to see the importance of his friends and even acknowledging them in his Nobel Prize acceptance speech. Will the character continue to develop and become even less like that original Sheldon from episode one?
While nobody wants Howard and Bernadette to break up, it seemed like their relationship was certainly straining towards the final few seasons. That being said, this could have been due to the intense stress and hardship that raising children brings.
It's a shame that the Big Bang Theory ended when it did, as it would have been heartwarming to see Howard and Bernadette's relationship grow even stronger as their children age (or heartbreaking to see it end).
When Penny first appeared on the show, she was an aspiring actress and this was her main goal for the first few seasons. However, Penny then discovered that she had real talent making sales in the pharmaceutical industry. That being said, Penny was only working in sales for the money, rather than the passion.
The question, however, is what does Penny want to do in the future? Will she be happy with family life?
In the episode "The Closet Reconfiguration," Howard and Sheldon discover a letter from Howard's father that was intended to be opened when he turned eighteen. Despite finding the letter, Howard decided against reading it and burned the letter in the sink.
As Sheldon was with Howard when the letter was discovered, only Sheldon knew what was in the letter. The gang then decided to each tell Howard a different story of what was written in the letter, with only one of the stories being true.
However, the audience, like Howard, never learn of what was actually written in the letter. What was actually written in the letter will have to remain a mystery.
There has been foreshadowing since episode one of The Big Bang Theory that Leonard and Penny will have children, "our babies will be smart and beautiful." But, throughout the 12 seasons, Penny has stated that she did not want to have children, leading to conflict with Leonard. However, in the final episode, Penny reveals that she is pregnant and happy about the prospect of becoming a mother.
While this will have no doubt pleased some fans of the show, the question remains 'what kind of parents will they be?' Both had fairly tough upbringings, so we can gather that they will want to stay clear of the mistakes of their parents. It's a shame that their parenting won't be seen on screen.