The Big Bang Theory / Season Ten

Leonard and Penny hold a second wedding to invite their friends and families to, resulting in significantly antagonized family relationships. Howard also has to deal with the Air Force taking an interest in his gyroscope design, as well as starting a family with Bernadette. Sheldon and Amy take their relationship to the next level by moving in together, while Raj finds himself at a crossroads after his father cuts him off financially.

Tropes present in The Big Bang Theory Season Ten

• 10-Minute Retirement: In "The Locomotion Reverberation", Sheldon considers quitting physics to become a train engineer.
• Abilene Paradox: In "The Comic-Con Conundrum", Leonard invites Penny to Comic-Con solely because he thinks she wants to go, and Penny accepts solely because she thinks Leonard wants her to come along. Both want the other to be happy, so it becomes an emotional Game of Chicken as neither wants to be the one to admit that they'd rather Penny not come.
• Aborted Arc: Raj's romance with the cleaning woman at the university. In an interview, Raj's actor made it look like it'd be a season-long arc, but she only appeared in a single episode and was never seen or mentioned again. She also was noticeably absent during the episode later in the season where Raj gathered all of his ex-girlfriends.
• Actually Pretty Funny: Even Beverly has to chuckle at Sheldon's remark about Alfred and Mary "fornicating like wrinkly old rabbits."
• Agony of the Feet: In "The Geology Elevation," Sheldon hurts his foot with a rock when it drops while he was trying to throw it. He then hurts his other foot kicking said rock in frustration.
• Amusing Injuries: Sheldon goes through a series of them throughout "The Geology Elevation." First he drops a rock on his foot while trying to throw it, then hurts his other foot kicking it. Then he slips and hits his head on a water fountain while he was trying to punch it. And finally, he hurts his hand punching (or rather, karate chopping a la Captain Kirk) Burt for saying that he could do better than Amy.
• Ascended Extra: Bert, a geologist colleague at Caltech (played by Brian Posehn), was seen in a few brief scenes in prior seasons but was only named in the credits in his first appearance. With this season he appears regularly, even with a small story of him earning a massive monetary award for a geology paper he wrote and how his life changed with the recognition.
• Aw, Look! They Really Do Love Each Other: In "The Dependence Transcendence" Sheldon is being difficult regarding his impending energy drink addiction and Leonard getting even more curt and sarcastic with him throughout the episode. But when Sheldon has a mild breakdown admitting he doesn't have the math to make their project work, Leonard is quick to comfort him and be supportive.
• Bankruptcy Barrel: Invoked on "The Comic-Con Conundrum." After reviewing Raj's spending, Sheldon suggests he buy a barrel and a pair of suspenders.
• Be Careful What You Wish For: Amy found out the hard way that living with Sheldon wasn't exactly a great idea. Especially at bedtime.
• The Big Damn Kiss: Ramona kisses Sheldon in "The Long Distance Dissonance." Sheldon reacts by flying to Princeton to propose to Amy.
• Black Bra and Panties: Referenced in "The Locomotion Reverberation."
  Penny: You guys ready to get crazy?
  Amy: Well, the bra under here ain't beige.
• The Bus Came Back:
  • Raj's ex-girlfriends: Lucy from Season 6 and Season 7, Claire from Season 9, Emily Sweeney from Season 7, Season 8 and Season 9 and the deaf Emily from Season 5.
  • Ramona Nowitzki from season two's "The Cooper-Nowitzki Theorem" returns, now a doctor, and still infatuated with Sheldon.
• Call-Back: The painting of Amy and Penny from Season 5 reappears in "The Property Division Collision."
• Calling the Old Man Out: Parodied. Raj is criticized by his father for being spoiled and relying on his money, rather than being self-sufficient. Raj decides to go cold turkey on his father's money and calls him up intending to chastise him for calling him spoiled. His father was just so happy to not have someone siphoning his money Raj didn't really get to make his point. "Dad, I'm trying to tell you off and you're ruining it with your joy and delight!"
• Cannot Keep a Secret: In "The Recollection Dissipation," Sheldon lost a notebook full of confidential information at a cowboy bar while high on cough medicine. Not only that, he also told it to everyone there (but not before making them Pinky Swear that they wouldn't tell).
• Catapult Nightmare: Sheldon in "The Veracity Elasticity," when he dreams that Leonard and Penny turned his old bedroom into a sex dungeon.
• Celebrity Paradox: A rather significant one, as Christopher Lloyd guest starred as a homeless man Sheldon recruits in a plan to get revenge on Leonard and Penny. Most of the time the big guest stars on the show are As Himself with a bit of Adam Westing involved (more minor celebrities, especially those not from geek cred shows, get original roles), but here they had Doc Brown from Back to the Future in their apartment and no one points out the similarity.
• Cerebus Retcon: Throughout the years, Sheldon's habit of knocking three times was funny. As of "The Hot Tub Contamination," we now know why he does this: so that people can get dressed in time before he enters a room. It stems from an incident of his youth, when he came home early, heard noises in his parents' room, and walked in on his father cheating on his mother.
• Character Development: While Sheldon still isn't ready for more sex, he is willing to have make-out sessions with Amy after an argument. He then decides to terminate the bathroom schedule when living with Amy and then during "The Veracity Elasticity" Sheldon makes the decision to permanently move in with Amy when he finds himself enjoying their cohabitation experiment.
  • Raj learns that being so needy and spoiled by his parents is not an attractive trait. Midway through the season he decides to go cold turkey on using his father's money, learning quickly that he had no idea how to manage money, and despite also having his own well-paying job was grossly in debt and simply cannot afford the lifestyle he was leading before. He eventually had to make the hard choice to not attend Comic Con that year, and avoided bumming off his friends on principle. While he still ended up living with Leonard and Penny for a time, he quickly made arrangements for a more permanent, modest garage apartment.
• Cliffhanger: The season finale ends with Sheldon proposing to Amy.
• Cold Turkeys Are Everywhere: Bernedette becomes depressed after taking Halley to the zoo on her last day of maternity leave because all the animals she sees take care of their young for longer than she is.
• Continuity Nod: Penny's short haircut in Season 8 is brought up in "The Geology Elevation." Turns out no one else liked it.
  • The horrifically oversized painting of Penny and Amy that Amy gave to her in season five returns as an item to discuss when it comes to moving apartments. It was always technically there, hanging on the Fourth Wall in Penny's original apartment, and Penny and Leonard have to hang it on the Fourth Wall of their apartment now.
  • The silly Aquaman costume Raj wore in the fourth season episode "Justice League Recombination" returns as a costume he wears while holding a sign advertising Stuart's comic book shop.
• Cute, but Cacophonic: Halley, Howard and Bernadette's baby, spends much of her time crying. It's disturbingly similar to how Debbie Wolowitz sounded.
• Daydream Surprise:
  • "The Romance Recalibration" begins with Leonard treating Penny to a romantic evening. Suddenly he burps loudly and Penny snaps back to reality, where Leonard is in his underwear playing video games.
  • The Stinger for "The Locomotion Reverberation" is Amy watching a shirtless Sheldon running a train. It then cuts to her taking Sheldon to the railroad camp.
  • Another stinger example: in "The Cognition Regeneration", Sheldon is walking on stilts, as he was trying to do earlier in the episode. Then he wakes up.
• Dump Them All: Inverted in "The Hot Tub Contamination." In conversation with Stuart, Raj claims he's back to being single and not by his own choice, implying that both Emily and Claire have ditched him. Which would explain why neither of them had been seen since the end of the previous season.
• Fallback Marriage Pact: When Raj worries that he'll never find love in "The Emotion Detection Automation", Howard jokingly says that if he and Bernadette ever broke up, Raj could marry him. When Raj asks why he would marry Howard instead of Bernadette after said break-up scenario, Howard responds that Stuart already claimed that option.
• "Fawlty Towers" Plot: Amy's apartment became unlivable after a water pipe burst, and as part of an experiment she and Sheldon lived together in Penny's apartment, while Leonard and Penny lived alone in Leonard and Sheldon's apartment. It was supposed to be a "five week experiment" but her apartment was finished two weeks early. She was enjoying living with Sheldon, and he also enjoyed it, so she didn't tell him and had to deflect his questions on when it would be done. Penny learned from Bernadette she had lying to Sheldon and slyly tried prying the truth from her, which lead into Amy making absurd claims about the dry wall becoming "wet wall" and that the construction crew was waiting for the "wall store" to have a sale.
• Foreshadowing: Early into the season Howard is concerned that the Military's interest in their gyroscope project will result in them taking the project and leaving the guys with nothing. Come episode 23 and this is exactly what happened.
• "Friends" Rent Control: An interesting inversion. It turns out using his father's money meant Raj was actually living well above his finances, as despite having a nice but modest apartment he was frivolous with expenses including a housekeeper, dog walker and a penguin he sponsors at a zoo. When he decides to stop using his father's money, he learns that he is massively in debt and can no longer afford his apartment.
• Game of Chicken: Leonard and Penny engage in an emotional variation when he invites her to Comic-Con, but she doesn't want to say she doesn't want to go, and he doesn't want to admit that he doesn't want her there, because each wants the other to be happy.
• Geeky Turn-On: Sheldon and Amy's relationship has gotten to the point where it revolves primarily around this. During their annual coitus on Amy's birthday their initial attempt got interrupted by Bernadette going into labor. When trying to rekindle the romance, Amy reveals some Harry Potter merchandise to get him back in the mood (although Sheldon was upset she went to Wizarding World without him). After the baby is finally born, they went to Wizarding World afterwards and Sheldon reveals it got him back in the mood. In another episode they have a fight over their experiment in living together, and Amy burns him so bad over his scientific method methodology that he suggests they go back to their apartment and make out.
• Gold Digger: Bert's girlfriend Rebecca in "The Separation Agitation" is considered this by the group, since they got together after Bert mentions winning the MacArthur Grant on his online dating profile. It ends up being deconstructed, as the group pressures Bert to dump her for this trope and he does so, only to regret it because he was happier with her, however superficial it may have seemed. The group ends up wondering how much different it really is to be with someone for their money versus their looks or intelligence.
• Gone Horribly Right: In "The Locomotion Reverberation," Sheldon has figured out a way to make the prototype smaller, which would mean extra work for Leonard and Howard. To get them out of their hair, Leonard gives him a certificate for a railroad camp (which set Leonard back $4,000). Unfortunately, Colonel Williams sees Sheldon's work and insists on making the changes, so now they have to get Sheldon back on board. Imagine their surprise when they discover that Sheldon wants to quit physics and be a railroad engineer full time.
• Goofy Suit: Raj wears his Aquaman costume to advertise the comic book store in "The Comic-Con Conundrum".
• Green-Eyed Monster: Sheldon is envious of Burt the geologist for winning the MacArthur Fellowship award in "The Geology Elevation."
• Is This Thing Still On?: A variant, Howard called up the Air Force colonel looking to meet with him and was seemingly asked about Raj and his immigration status. When Raj freaks out, Howard reveals he's still on hold.
• Like Father, Like Son: Or daughter, in this case. It's mentioned that Penny and Wyatt share a similar fondness for alcohol.
• Minor Flaw, Major Breakup: While not a break-up, Penny and Leonard admit to the rest that they had a major fight over the holidays, one of the worst they ever had. It turned out they were watching Luke Cage (2016) together and Leonard found out she watched two episodes ahead of him. After thinking about it, they admitted that they were also strung out from a stressful evening getting a Christmas tree for their apartment (Leonard struggled chopping it down, the tree slid off their car roof, Leonard passed out bringing it up three stories and once they got it in they found a rodent still living in the tree).
• Nap-Inducing Speak: In "The Holiday Summation," Stuart is able to put Howard's baby to sleep, claiming that his talking puts people to sleep. In The Stinger, he starts telling what he did during Christmas and everyone pretends to fall asleep.
• Nerds Speak Klingon: Leonard and Sheldon speak in Klingon to hide their conversation from Amy and Penny in "The Veracity Elasticity". Amy and Penny, in turn, use Ubbi Dubbi for the same purpose.
• Not So Above It All:
  • Leonard and Penny ended up getting into a fight over who was putting more effort into the relationship and romance now that they're married (Penny was feeling Leonard had given up and was neglecting her while Leonard felt she was just expecting him to reach out while never doing the same). After a long conversation they went to Sheldon and, with some embarrassment, asked him to write up a Relationship Agreement so they can get ahead of such problems.
• Once a Season: Started last year, but In-Universe Sheldon has agreed to sexual relations with Amy on her birthday. This year their efforts to get things going are interrupted by Bernadette going into labor.
• One-Steve Limit: Played with in "The Emotion Detection Automation." Raj gathers his ex-girlfriends, wich includes two Emilys. He calls one Redheaded Emily, but then realizes the other Emily also has red hair, so he calls her Redheaded Emily Junior.
• O.O.C. Is Serious Business: In "The Long Distance Dissonance," the guys get concerned about Sheldon when Ramona touches his hand and he doesn't clean it with Purell immediately afterwards.
• Overly Long Gag: The ending of "The Long Distance Dissonance," when Sheldon reacts to Ramona kissing him by excusing himself, then taking a taxi to LAX and board a flight to New Jersey just to propose to Amy.
• Peanuts: In "The Locomotion Reverberation," Leonard tries to trick Sheldon into solving an equation by solving it wrong; he points out that a squiggle in the solution isn't a mathematical symbol, but Charlie Brown's hair. Sure enough, Sheldon sees the equation and corrects it by drawing Charlie Brown's face around the squiggle.
  Sheldon: Nice try, blockheads.
• Primal Scene: In "The Hot Tub Contamination," Sheldon confesses to Penny that he once saw his father making love to a woman other than his mom and he never spoke to him again. This is also why he always knocks three times; the first knock was traditional, and the other two are to give them time to put on their pants.
• Rail Enthusiast: Sheldon's love of trains is front and center in "The Locomotion Reverberation", where he considers quitting theoretical physics to become a train engineer.^note "Not a goofy one like Howard."
• Reactive Continuous Scream: In a variation, Halley continues to cry and Bernadette can't figure out how to get her to stop, making her cry from being stressed out. At one point Bernadette is crying in her room, prompting Halley to cry, and eventually Howard starts crying along with them.
• Reasonable Authority Figure: Colonel Williams is completely understanding when Howard, Sheldon, and Leonard confess that they need more time than expected to perfect their gyroscope and grants it to them with no strings attached.
• Romantic Runner-Up: In "The Emotion Detection Automation", Raj discovers that all his exes found better relationships after they broke up with him.
• Silk Hiding Steel: It turned out to be a good thing having Bernadette officiate the family wedding, as she quickly got the wedding party in line after some snide comments.
• Single-Target Sexuality: Sheldon has shown romantic interest in exactly one person, Amy. When she leaves for a summer fellowship at Princeton, he ends up spending time with Dr. Ramona Nowitzki, who previously showed an obsessive romantic interest in him (which was in the second season, and her interest was clearly unrequited). This causes the entire group some panic, as in Amy's words "I've been smacking that ketchup bottle for a long time. All she's got to do is tip it over and point it at her fries."
• Sleep Cute: In "The Holiday Summation," Bernadette tries to put her baby to sleep, and finds that she can lie down with her inside the crib.
• So Proud of You: Raj's father says this when Raj claims he would become more self-reliant by no longer taking his father's money. Raj isn't filled with pride at the way his father expresses his opinion about Raj's decision, though.
• Surprisingly Realistic Outcome:
  • In an effort to undercut an MIT team, Sheldon claims he, Howard and Leonard could miniaturize their gyroscope for the Air Force in 2 months. After desperately scrambling to find a way, they're finally forced to admit that it will take much longer. Their military contact just shrugs and accepts the new schedule.
    Col. Williams: You guys think you're the first government contractors to miss a deadline? We're still waiting on a giant space laser Reagan ordered to beat the commies.
  • Two girls aren't really going to be interested in dating the same guy, as Raj found out the hard way.
  • Someone with Sheldon's issues and personality quirks would be hard to live with. As a result, Amy struggled to have a good night's sleep and wanted to not do it anymore. One wonders how Leonard was able to do it for so long...
  • Raj was careless with money because he was spoiled by his parents. As soon as he is cut off, his finances are so bad that he has to take odd jobs from Stuart and move in with Leonard and Penny.
  • After spending an entire year working on their gyroscope, the guys are happy to have a finally working prototype. But when they show up the next day, they discover the lab cleaned out and Colonel Williams telling them that the military is moving on and they are not needed for the next stage. They protest but he makes it clear that the military only cared for the project, never for them.
  • The guys spent months working on a gyroscope and got it down to the specifications agreed upon by them and the Air Force. Sheldon began some new equations that would reduce the current design by another 20%, but would be months of additional work and Leonard and Howard pushed him away. Col. Williams comes by to review the progress and catches Sheldon's preliminary math, and the promise of an even smaller design makes him want them to start over. It's far from the first time upper management decides on a change that sets back all the current development.
• Two-Timer Date: Sheldon does a variation in "The Recollection Dissipation," going back and forth between Leonard and Howard with the guidance system and Amy with her research. He ends up getting sick and going on a cough syrup-fueled bender during which he loses a notebook with confidential information at a cowboy bar. Lampshaded by Penny.
  Penny: Aw, looks like someone invited two dates for nerd prom.
• Vocal Dissonance: Howard's baby girl Halley is identifiable by her crying, done in the same gruff voice as his late mother.
• Wham Line: At the very end of the last episode of the season.
  Sheldon: Amy, will you marry me?
• Wham Shot: In the last episode of the season, Sheldon is kissed by Ramona Nowitzki, causing him to immediately fly to New Jersey to visit Amy. When she opens the door, he is already on one knee with an engagement ring.
• What Did I Do Last Night?: In "The Recollection Dissipation", Sheldon wakes up after taking cough medicine and finds that he's naked from the waist down, and has lost a notebook full of confidential information about the guidance system. He finds it at a cowboy bar, where he also told everyone there about the guidance system.
• White Sheep: Penny's brother Randall went to jail for cooking meth, and their mother Susan is concerned that among all the academics of their in-laws they'll come across as white trash.
• Your Approval Fills Me with Shame: Howard shops around a Stephen Hawking remote control toy to see if others consider it offensive. Bernadette, Raj, Amy and Leonard all think it is, but it's Barry Kripke (who also wants to drive it into the women's restroom) thinking it's hilarious that convinces Howard that it is offensive.
• You're Drinking Breast Milk: Bernadette actually has to tell Stuart not to drink her breast milk.