I agree with Jeff. The finale was hardly “perfect”. I thought they took the safest route possible; and there were only a few good laughs. Some of it was predictable; winning the Nobel and fixing the elevator. The prize ceremony wasn’t even particularly interesting. Having each friend stand and be recognized at a Nobel ceremony seemed way of place…even for Sheldon. The writers were obviously struggling this last season for new material , and the finale was no exception. I still think Raj should have ended up with ‘someone’, as they felt the need to pair everyone else off during the series. (Even Stuart got a girl.). All in all, I found the finale wanting. I thought going in that I might burn it to DVD as an episode to keep to watch again. I’ll pass.
One of the recurring plot lines is the relationship between Leonard and Penny. Leonard becomes attracted to Penny in the pilot episode and his need to do favors for her is a frequent point of humor in the first season. Meanwhile, Penny dates a series of muscular, attractive, unintelligent, and insensitive jocks. Their first long-term relationship begins when Leonard returns from a three-month expedition to the North Pole in the season 3 premiere. However, when Leonard tells Penny that he loves her, she realizes she cannot say it back. Both Leonard and Penny go on to date other people; most notably with Leonard dating Raj's sister Priya for much of season 4. This relationship is jeopardized when Leonard comes to falsely believe that Raj has slept with Penny, and ultimately ends when Priya sleeps with a former boyfriend in "The Good Guy Fluctuation".
Wil Wheaton brings William Shatner on his Professor Proton show to meet Sheldon, who gets so excited that he vomits on Shatner. Going to Wil to apologize, he finds Wil hosts a Dungeons & Dragons group with his celebrity friends including Shatner. Finding out Stuart is in the group and never told them, the guys make Stuart panic and quit. Wil secretly invites Leonard who discovers that the group also includes Shatner, Kevin Smith, Joe Manganiello and Kareem Abdul-Jabbar. Leonard tells Penny, who tells Amy and Bernadette, all three women having a crush on Manganiello. Because of that indiscretion, Wil kicks out Leonard and admonishes the guys for using him for his connections, and says that one of the worst things about being a celebrity is not knowing whether someone will like him for himself. To apologize, the guys invite Wil to play D&D with them at Leonard’s apartment, but Wil, secretly in the middle of a game with Penny, Amy and Bernadette and the group, politely turns them down, before allowing the girls to send them a photo of the events as payback.
Amy enthusiastically accepts Sheldon's marriage proposal. However, when dining with Amy's colleagues later that night, Sheldon is offended that they are more impressed with Amy's work than his own. With help from Stephen Hawking, Sheldon later comes to grips with the fact that he will not always be the center of attention in the marriage. Bernadette is shocked to realize that she is pregnant again. She and Howard are not thrilled at the idea of having another baby so soon after their first. They attempt to convince Leonard and Penny to have a child as well, but are rebuffed.
The fourth season's second half began on June 30, 2011. Season 5 began airing on November 3, 2011, at 8:00 p.m. as part of E4's Comedy Thursdays, acting as a lead-in to the channel's newest comedy, Perfect Couples. Episode 19, the highest-viewed episode of the season, attracted 1.4 million viewers. Season 6 premiered on November 15, 2012, with 1.89 million viewers and a further 469,000 on the time shift channel, bringing the total to 2.31 million, E4's highest viewing ratings of 2012, and the highest the channel had received since June 2011. The sixth season returned in mid-2013 to finish airing the remaining episodes. Season 7 premiered on E4 on October 31, 2013 at 8:30pm and hit multiple ratings records this season. The second half of season seven aired in mid 2014. The eighth season premiered on E4 on October 23, 2014 at 8:30 p.m. During its eighth season, The Big Bang Theory shared its 8:30 p.m. time period with fellow CBS comedy, 2 Broke Girls. Following the airing of the first eight episodes of that show's fourth season, The Big Bang Theory returned to finish airing its eighth season on March 19, 2015.
Sheldon and Amy go on their honeymoon to New York City, starting with Legoland New York. Sheldon's insistence on scheduling their marital relations stresses Amy. He says he only does it to remind himself to be intimate with her. They compromise by letting him make a schedule without sharing it with her. Leonard and Penny discover Mr. Larry Fowler (Teller) in Sheldon and Amy's apartment hiding from his wife (Kathy Bates). Leonard notices parallels in his own marriage, which offends Penny. Leonard apologizes, and Penny convinces Mrs. Fowler to give her husband a break. When Mrs. Fowler wants to hang out with her regularly, Penny scares Larry out of the building. Raj instigates a Twitter feud with Neil deGrasse Tyson but is scared off when confronted over the phone. Neil then calls Bill Nye to scare him, too.
“I was there the moment when Leonard and Penny met. He said to me that their babies would be smart and beautiful. And now that they’re expecting, I have no doubt that that will be the case,” Sheldon says, accidentally revealing the baby news even before Penny’s parents know. “I apologize if I haven’t been the friend that you deserve. But I want you to know, in my way, I love you all.”
In the show, the song "Soft Kitty" was described by Sheldon as a song sung by his mother when he was ill. Its repeated use in the series popularized the song. A scene depicting the origin of the song in Sheldon's childhood is depicted in an episode of Young Sheldon, which aired on February 1, 2018. It shows Sheldon's mother Mary singing the song to her son, who is suffering with the flu.
Anu wants to have sex with Raj, but he gets so nervous in the leadup, that his selective mutism returns. Confessing to her, she is very understanding, revealing an unusual secret of her own. The next morning, he is able to have sex with her in the shower. Sheldon attempts to bond with his father-in-law, but Larry is more impressed with Howard's magic tricks, causing a jealous Sheldon to spend time with Mrs. Fowler. They bond after finding out Amy has been using Sheldon as an excuse to avoid her mother, though he does gently advise her to forgive her daughter like he would his wife. A remorseful Amy invites the Fowlers over for thanksgiving, where Sheldon and Mrs. Fowler continue to bond over Larry's ineptitude with magic.
After learning Sheldon went behind their backs to work with the military again, Leonard and Howard say Sheldon is like Thomas Edison, taking credit for others' ideas, while they are more like Nikola Tesla. Leonard and Howard bring in Barry Kripke to help create a better idea than Sheldon's, but Kripke goes to the military himself, cutting all three of them out. Meanwhile, Bernadette fears Ruchi is trying to steal her projects at work while she is on maternity leave and enlists Raj to spy on her. Though he finds proof that Ruchi may be stealing from Bernadette, Raj tries to defend Ruchi like a boyfriend would, pointing out Bernadette's hypocrisy as she would most likely have stolen from other people's projects as well. Ruchi is not happy about this and promptly dumps Raj.
Howard and Raj are still fighting, so Howard dis-invites Raj to Halley's birthday party. However, when Stuart pulls out as party planner at the last minute, Raj agrees to plan the party, which doesn't turn out too well due to Halley being asleep, Bernadette being on bed rest, and no people turning up. When Howard and Raj get into a shoving match in the party's bounce house, they end up letting out their frustrations, but also having fun and reconciling. Leonard is depressed upon receiving his successful brother's Christmas card and attempts to make a list of what he and Penny accomplished this year, not coming up with much. This prompts them to think about their plans for the future, so they decide to go on trips and achieve more out of life together before starting a family. Sheldon cooks Amy a Little House on the Prairie-themed birthday dinner, which gives them both food poisoning. They eventually recover enough to attend Halley's birthday party with the others, where they have fun in the bouncy castle and then have sex in Howard and Bernadette's house.
Howard dresses as Sheldon for Halloween at work, hurting Sheldon's feelings. When Howard does not apologize, Amy and Sheldon dress as Bernadette and Howard at Penny and Leonard's party, angering Bernadette. Sheldon and Bernadette later bond over their painful childhood memories. Leonard is upset that Penny does not seem to remember that their first kiss was on Halloween. Penny later admits she does remember, but does not like to think of their first kiss as an unromantic drunken hookup. She likes to imagine their first kiss was one they shared on Leonard's birthday, which pleases him.
Sheldon's mother Mary refuses to attend his wedding unless he invites his older brother George, with whom he is no longer speaking. Sheldon and Leonard fly to Texas to talk to George, who now owns a chain of tire stores. He refuses to attend and later explains to Leonard and Sheldon that the family sacrificed a lot to fund Sheldon's education, and he was stuck caring for their mother and sister Missy after their father died while Sheldon was in college. Sheldon never thanked him for this. Leonard takes George back to the hotel room where Sheldon apologizes for what he did and the brothers reconcile. George agrees to attend the wedding. Meanwhile, Howard and Bernadette's children contract pinkeye, infecting everyone except Penny, much to Amy's fury.
Warner Bros. Television controls the online rights for the show. Full episodes are available at tv.com, while short clips and recently aired full episodes are available on cbs.com. In Canada, recent episode(s) and pictures are available on CTV.ca. Additionally in Canada, the first six seasons are available for streaming on Bell Media's CraveTV. After the show has aired in New Zealand the shows are available in full online at TVNZ's on demand web service.
Filming proceeds smoothly – makeup artists do touch-ups, a prop master replenishes the pickle supply – with humor and camaraderie between takes. When a reshoot is needed because Simon Helberg, who plays Howard, held his napkin in the wrong hand, Kaley Cuoco, who plays Penny, lifts her food box high and mockingly asks, “Does it go over my head? I don’t remember.”
Leonard's mother Beverly visits, and he is thrilled when she takes an interest in his work. However, when he learns that she is doing research on him for a new parenting book, he is furious. He prepares to tell her how she let him down over the years, but instead chooses to accept and forgive her, and forgive himself for holding onto that resentment for so long. Beverley is touched that he forgave her and they share a genuine hug. Meanwhile, Anu gets a job offer in London. Raj prepares to fly out and propose to her, ready to follow her if she accepts. Howard stops Raj at the airport, saying there is a better match out there for him, convincing Raj to return home. Stuart and Denise are bothered by her creepy roommate Mitch, while Bernadette and Howard are tired of Denise constantly staying overnight with Stuart at their house. Stuart says he is ready to move in with Denise, and they say they love each other while convincing Mitch to move out.
After Neil Gaiman tweets about Stuart's comic book store, it becomes very popular, and the crowds upset Sheldon. Stuart hires an assistant manager named Denise and she impresses Sheldon with her comic recommendations. Amy goes to her for information on comics to connect to Sheldon but when she tries to tell him, he says he's talked enough about comics with Denise. The store's popularity causes Stuart to be unable to babysit for Howard and Bernadette's date night. They try to have another at home, but Stuart shows up so they hurriedly go out. Meanwhile, as Raj sets up a telescope, Penny sees a new comet. Raj takes sole credit for the discovery, angering Penny. Leonard tries to defend her but feels sorry for hurting Raj's career. Penny confronts Raj herself and he agrees to share credit after Penny doesn't give in like Leonard.
In the episode "The Launch Acceleration", Amy tries to use her "neurobiology bag of tricks" to increase the attraction between herself and Sheldon. In the final fifth-season episode "The Countdown Reflection", Sheldon takes Amy's hand as Howard is launched into space. In the sixth season first episode "The Date Night Variable", after a dinner in which Sheldon fails to live up to this expectation, Amy gives Sheldon an ultimatum that their relationship is over unless he tells her something from his heart. Amy accepts Sheldon's romantic speech even after learning that it is a line from the first Spider-Man movie. In "The Cooper/Kripke Inversion" Sheldon states that he has been working on his discomfort about physical contact and admits that "it's a possibility" that he could one day have sex with Amy. Amy is revealed to have similar feelings in "The Love Spell Potential". Sheldon explains that he never thought about intimacy with anyone before Amy.
Johnny Galecki as Leonard Hofstadter: An experimental physicist with an IQ of 173, who received his PhD when he was 24 years old. Leonard is a nerd who loves video games, comic books, and Dungeons & Dragons. Leonard is the straight man of the series, in which he shares an apartment in Pasadena, CA, with Sheldon. Leonard is smitten with his new neighbor Penny when they first meet, and they eventually marry.
When Penny tells Leonard he needs to be more assertive in making decisions for himself, he starts standing up to Sheldon over small things. His confidence makes him want to demand the university support his idea for a plasma physics project. He threatens to quit if the university refuses, alarming both Sheldon and Penny, who consider this to be a risky career move. Sheldon is conflicted on whether or not he is being selfish over Leonard's decision, but Amy suggests that the fact that he is worried over Leonard's motivation proves that he does care about him, which he acknowledges. President Seibert refuses the project, but in order not to lose Leonard, gives him co-leadership over a photon entanglement project, leaving Leonard proud of himself and Penny impressed. Meanwhile, Raj shows Anu his lab, and suggests one possible answer for something he's seen in space might be alien life. When someone mentions this at his observatory presentation, the scientific community starts mocking him as a conspiracy theorist. Raj points out scientists should consider all possibilities when seeking the truth, though this causes people to think he believes in the Loch Ness Monster.
Kunal Nayyar as Rajesh Koothrappali: A particle astrophysicist originally from New Delhi, India. Raj is initially unable to talk to women unless he drinks alcohol. Raj also has very feminine tastes and often takes on a stereotypical female role in his friendship with Howard as well as in the group of four men. Raj later dates Lucy (Kate Micucci), who also suffers from social anxiety, but it eventually ends; he later speaks to Penny without alcohol and thus overcomes his selective mutism. He begins dating Emily and their relationship later becomes exclusive. Raj also has a Yorkshire Terrier named Cinnamon.
In March 2017, CBS renewed the series for two additional seasons, bringing its total to twelve, and running through the 2018–19 television season. On August 22, 2018, CBS and Warner Bros. Television officially announced that the twelfth season would be the series' last. This stems from Jim Parsons' decision to leave the series at the end of the season if the show were to have been renewed for a thirteenth season. The series concluded with an hour-long finale consisting of two back-to-back episodes on May 16, 2019. A retrospective, hosted by Johnny Galecki and Kaley Cuoco, aired at 9:30 P.M. ET/PT, the night of the finale, following the season two finale of Young Sheldon.
According to Steve Holland who is the show-runner starting with this season, Wil Wheaton will return in this season since his absence from Season 10. And this has confirmed to be true since it has been stated that he reappeared in "The Proton Regeneration" (S11E6), along with Professor Proton, their first appearances since "The Opening Night Excitation" (S9E11) and "The Celebration Experimentation", respectively and a span of 43 episodes and a span of 37 episodes, respectively. Wil also returned in the 15th episode. Wil will also return for Sheldon and Amy's Wedding.
By season seven, Galecki, Parsons, and Cuoco were also receiving 0.25% of the series' back-end money. Before production began on the eighth season, the three plus Helberg and Nayyar, looked to renegotiate new contracts, with Galecki, Parsons, and Cuoco seeking around $1 million per episode, as well as more back-end money. Contracts were signed in the beginning of August 2014, giving the three principal actors an estimated $1 million per episode for three years, with the possibility to extend for a fourth year. The deals also include larger pieces of the show, signing bonuses, production deals, and advances towards the back-end. Helberg and Nayyar were also able to renegotiate their contracts, giving them a per-episode pay in the "mid-six-figure range", up from around $100,000 per episode they each received in years prior. The duo, who were looking to have salary parity with Parsons, Galecki, and Cuoco, signed their contracts after the studio and producers threatened to write the characters out of the series if a deal could not be reached before the start of production on season eight. By season 10, Helberg and Nayyar reached the $1 million per episode parity with Parsons, Galecki, and Cuoco, due to a clause in their deals signed in 2014.