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The Untold Truth Of The Big Bang Theory

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The Big Bang Theory quietly debuted on CBS in 2007. Once reruns of the show started running around the clock on local stations and cable, the ensemble sitcom exploded in popularity. While those reruns dominate the list of most-watched cable shows, the original episodes routinely rank near the top of the weekly network TV ratings — it's been the most-watched sitcom on TV for years.

It's a low-key security blanket of a show for millions of Americans who enjoy the personal and professional adventures of the Caltech-based group of (mostly) super-genius scientists, including prickly and particular theoretical physicist Sheldon Cooper (Jim Parsons), friendly experimental physicist Leonard Hofstadter (Johnny Galecki), lovelorn and sensitive astrophysicist Raj (Kunal Nayyar), and socially awkward neurobiologist Amy Farrah Fowler (Mayim Bialik). 

Here's a look at some stories and scandals behind the scenes of the America's favorite sitcom about science nerds and the people who love them.

The first pilot episode is unrecognizable

The Big Bang that's aired for a decade-plus is very different from the pilot episode presented to CBS in 2006. While he's now depicted as largely asexual and mystified by romance (and other seemingly inefficient human pursuits), Sheldon (Jim Parsons) was outspokenly sexually active in the pilot. There was also no Penny (Kaley Cuoco); instead, the attractive neighbor role was filled by a tough, not-very-friendly woman named Katie (portrayed by Amanda Walsh). Even the optics were different — yet to discover his trademark hoodies, Leonard (Johnny Galecki) wore suits. There was one other noticeable difference: The theme song was Thomas Dolby's 1983 hit, "She Blinded Me With Science" (which is just a bit on the nose). CBS passed, but asked creators Chuck Lorre and Bill Prady to rework the show and submit another pilot. They did, extensively — and added in a new theme song from Barenaked Ladies — which made it to the network's fall schedule in 2007.

Melissa Rauch doesn't sound like that in real life

Over the years, the show has mined a lot of comedy from Bernadette's voice. When she's just talking to Howard or her friends, she speaks in a quiet, mousy, high-pitched way. But when she gets angry, she switches to loud (yet still high-pitched) moments of screaming rage. Neither of those voices come naturally to the actress behind Bernadette, Melissa Rauch, who sounds nothing like Bernadette in real life. In fact, her regular, off-screen speaking voice is quite normal — it's reminiscent of co-star Kaley Cuoco's, just a bit lower.

Rauch took her inspiration for Bernadette from a source close to home: her own mother. Although the two women share vocal DNA, they have one major difference — Bernadette lacks Rauch's mother's New Jersey accent. "Tonally, it's very similar," Rauch explained at a PaleyFest event. This means that when Bernadette would imitate Howard's late mother, who spoke with a Jersey accent, she was likely doing a fully accurate impression of her mom.

Big Bang Bucks

In 2014, contract re-negotiations between the cast and production company Warner Bros. TV delayed production on the show. Ultimately, CBS renewed the sitcom for three additional seasons, and the show's three leads — Jim Parsons, Johnny Galecki, and Kaley Cuoco — secured a salary of $1 million... per episode... each. Meanwhile, the show's male supporting actors (who'd been with the show since day one) also had to renegotiate their contracts. Simon Helberg (Howard) and Kunal Nayyar (Raj) bargained collectively, and both wound up with salaries of around $750,000 per episode. Thankfully for all parties involved, that settlement was reached the day before their old contracts ran out. Had Helberg and Nayyar not not accepted the dealBig Bang writers would have been ordered to write their characters off the show.

That leaves the other two major, long-term Big Bang Theory cast members, Melissa Rauch and Mayim Bialik. They both joined the show later on in its run, and up until the 2016-17 season, both raked in a (relatively) meager $200,000 per episode. Then they got a major pay raise, thanks to their very generous co-stars. For the show's 11th and 12th seasons, the highest-paid cast members agreed to a pay cut down to $900,000 an episode each, with the expressed intent that the extra money went to giving Rauch and Bialik a raise, who would then earn about $450,000 an episode. (Best. Coworkers. Ever.)

Johnny Galecki and Kaley Cuoco secretly dated for years

In the early years of The Big Bang Theory, Johnny Galecki dated one of the loveliest actresses in all of television, while Cuoco dated a handsome TV star herself. And both managed to keep their relationship secret. Surprise: Galecki and Cuoco dated each other, concurrent with their characters' budding romantic interest in one another... and almost nobody knew about it.

It wasn't until 2010, well after the couple amicably split, that either said anything publicly about their time together. Cuoco told company magazine CBS Watch! that she had dated Galecki "for almost two years. It was such a huge part of my life and nobody knew about it." That included never going "anywhere together." Three years later, Galecki gave his side of the story to CBS Watch! "We're dear friends, still," he said. "Kaley's not just an ex, she's a part of my life." So why were they so private about things? "I just don't like to speak about it," Galecki said. "And not because I'm trying to be enigmatic; I just worry that it will conflict with people's acceptance of Leonard and Penny."

The show starring Blossom is obsessed with Blossom

In the first season episode "The Bat Jar Conjecture," Sheldon quits the Big Bang boys' physics bowl team. The guys need a replacement, and fast, and Raj aims high in his suggestion for a replacement, naming "the girl who played TV's Blossom," because she'd gone on to earn a Ph.D in neuroscience in real life. "TV's Blossom" is actress Mayim Bialik, of course... who, a couple years after that episode aired, joined the cast of The Big Bang Theory as Amy Farrah Fowler (who also happens to be a neuroscientist). 

Oddly, that's not the only time The Big Bang Theory has suggested that the television series Blossom — as well as a character on the show who looks exactly like the star of that show — exists in the show's universe. On a sixth season episode — long after Bialik joined the cast — Sheldon and Amy make a Venn diagram to determine a mutually agreeable Halloween "couples costume." Appearing in the list of pop culture couples Amy likes: "Blossom and Joey." (Amy certainly wouldn't have to do much to nail that look.)

Is Soft Kitty a copyright infringing kitty?

Co-creator Bill Prady says he heard Sheldon's special calm-down song being sung at his daughter's preschool. Assuming it was in the public domain, he added it to the show, where it's been used multiple times and on scores of Big Bang merchandise. In December 2015, however, the family of a New Hampshire preschool teacher named Edith Newlin sued CBS and Bill Prady Productions for copyright infringement, alleging they lifted lyrics without permission from a song Newlin wrote in the 1930s called "Warm Kitty." The main difference: The Newlin piece begins, "Warm kitty, soft kitty, little ball of fur." The Big Bang version starts out, "Soft kitty, warm kitty, little ball of fur." It appeared as such in a 1937 book called Songs for the Nursery School.

In March 2017, U.S. District Judge Naomi Reice Buchwald dismissed the suit, ruling that Prady hadn't violated any copyright laws because Newlin's descendants couldn't actually prove that they had a copyright on "Warm Kitty."

You're never going to see those babies again

In the middle of the tenth season in 2016-17, a new character joined The Big Bang Theory: Halley, the newborn baby daughter of Howard and Bernadette. And while Howard and Bernadette's lives have been radically altered by starting a family, the baby itself doesn't show up on screen too much... like, ever. Showrunner Steve Molaro says that, apart from the Very Special Episode featuring Halley's birth, that baby will only ever be heard, and not seen, screaming and crying offscreen. It's a tribute to Carol Ann Susi, the unseen actress who played Howard's similarly always-screaming mother. Susi died in 2014, and her character subsequently did, too. Molaro added that "it also means we don't have to have a baby on set, so it solved lots of problems."

In 2018, Bernadette gave birth to baby number two, a boy named Neil (as in Armstrong, Gaiman, and Diamond). Executive producer Steve Holland told Entertainment Tonight that he'll probably honor Molaro's "no babies allowed" policy. "I'm not super excited to have someone haul their newborn twins and shove them in front of a camera," Holland said.

There's been a lawsuit over the theme song

Canadian pop-rock band Barenaked Ladies is responsible for "The Big Bang Theory Theme," which generates revenue for the band every time it's played on an episode of The Big Bang Theory, which is quite often. The band has even recorded an extended version of it and included it on the band's greatest hits album. The catchy number has since made its way into the band's set list when they play live. But it's all not without controversy. Although longtime Barenaked Ladies member Steven Page left the band in 2009, he says he was promised a 20 percent cut of any profits the song generated. According to Page, he hasn't seen a dime of Big Bang theme song money. He filed suit, alleging that front man Ed Robertson has kept all the money for himself. According to legal documents, Page believes he's owed somewhere in the neighborhood of $1 million by the rest of the group, with whom he once, ironically, recorded the song "If I Had a Million Dollars."

It generated a spinoff

Almost every successful sitcom has launched a spinoff or two. Cheers led to Frasier, Happy Days spawned Laverne & Shirley, and soon The Big Bang Theory will get one, too. CBS ordered Young Sheldon, a comedy that focuses on prickly genius Sheldon Cooper, back when he was a prickly child genius living in Texas. Iain Armitage (Big Little Lies) stars as young Sheldon, while adult Sheldon's portrayer, Jim Parsons, narrates episodes. Unlike The Big Bang Theory's multi-camera, laugh track-laden setup, Young Sheldon is a single-camera, laugh track-free show, akin to Modern Family or Scrubs.

When Cuoco Met Parsons

Most of the cast of The Big Bang Theory are seasoned television veterans. Some, such as Mayim Bialik, Johnny Galecki, and Kaley Cuoco, all started acting when they were children. They've all been knocking around Hollywood for a while, and some had pre-existing relationships before Big Bang. (Bialik, then of Blossom, invited Galecki, then of Roseanne, to her sixteenth birthday, but he missed it because he got in a motorcycle accident on the way. And Galecki and recurring guest star Sara Gilbert played a couple on Roseanne for years.) 

Jim Parsons and Kaley Cuoco didn't know each other at all before The Big Bang Theory, and they actually met for the first time while auditioning for the show on the same day. Cuoco introduced herself, but Parsons was busy, trying to figure out how to work his new Blackberry device. Cuoco said she remembered thinking Parsons would make a "hilarious Sheldon," although it's amusingly ironic that the man who would soon play a brilliant scientist couldn't get a simple consumer gadget to function properly.

The Big Bang Theory actor who doesn't care for The Big Bang Theory

Mayim Bialik joined the series as neuroscientist Amy Farrah Fowler in season 3 and very slowly became a love interest, then girlfriend, and then, improbably, a spouse for Sheldon, as well as a hopelessly devoted BFF to Penny. The Big Bang Theory had been on TV for a while by then, but Bialik hadn't quite managed to catch an episode. Bialik went in to the show cold — totally cold. "I had never seen The Big Bang Theory. I knew it was a big deal because my manager told me, like, 'Try and get this part,'" Bialik said. As of 2016, she claims to have still not seen any Big Bang episodes produced before she joined, not to mention most of the ones that she actually appears in. "I don't have TV, so I don't really watch," Bialik said. (Sure, but she probably knows where to score some tapes.) 

Wrong Chuck, Jim

For all of Chuck Lorre's success as a TV creator and producer, Jim Parsons had never heard of him when he was about to audition for The Big Bang Theory. Well, actually, he thought the show was created by a different, similarly-named successful show business type. Parsons said on The Late Show with David Letterman that when his agent called him to say he'd landed an audition for the new "Chuck Lorre show," Parsons got confused and thought the agent meant Chuck Woolery, the host of game shows like Scrabble and Love Connection. That made Parsons less than enthusiastic about the audition — after all, he figured it was a sitcom written by a game show host who hadn't worked prominently in TV since the 1980s. "I thought, why are they so excited about it?" Parsons admitted. "We should see what the man has to offer before we're like, 'It's a new Chuck Woolery pilot!'"

The Belarus Bang Theory

Every episode of The Big Bang Theory ends with a "title card" from Chuck Lorre. He writes a new one each time, and while it only appears on screen for a second or two, he uses it as a sounding board. In 2010, one such card reported on Lorre's discovery of a TV show from the Eastern European nation of Belarus called The Theorists. The premise, according to Lorre's title card: "a sitcom about four nerdy scientists who live next door to a beautiful blonde waitress. The characters are named Sheldon, Leo, Hovard, Raj, and Natasha." The opening sequence for the show: "a rapid-fire montage of images which takes us from the dawn of time to the present moment." Lorre was convinced that The Theorists was majorly cribbing from The Big Bang Theory, including the fact that "each episode appears to be a Russian translation of a Big Bang Theory episode." Lawyers at Warner Bros. Television told Lorre there was little that could be done because the production company responsible for The Theorists was owned by the Belarusian government. (The show was canceled before long anyway.)

There's a species of jellyfish named after the show

In 2011, a photographer named Denis Riek spotted a tiny organism in the Brunswick River in the Australian state of New South Wales. Riek knew it was a jellyfish but couldn't readily identify it, so he sent his photos to jellyfish expert Dr. Lisa-ann Gershwin. After two years of research, Gershwin and her colleague, taxonomist Peter Davie, confirmed that the 15-millimeter creature was a previously undiscovered jellyfish. As one of the discoverers, Gershwin got to help name the species, and she went with Bazinga rieki. The first part of the name refers to Sheldon Cooper's catchphrase cry of triumph, "Bazinga!" — not unlike that of a scientist shouting "Eureka!" at a moment of great discovery. But Dr. Gershwin says it also refers to a musical instrument. "The name bazinga also refers to a seven-string harp, and the straight radial canals of this new species are reminiscent of such strings." (Bazinga!)


Biologists from the Universidade Federal de Uberlandia in Brazil announced the discovery of a new bee in 2013: the orchid bee. It so closely resembles another species of bee, the Euglossa ignita, that the researchers decided to go ahead and give the orchid bee its own official scientific name of Euglossa bazinga.  Sheldon most often uses "Bazinga!" as a kind of "gotcha!" when he tricks someone or plays a prank on them. The biologists thought the word was a perfect way to describe such a tricky bee. That makes it one of few insects on Earth to ever be named after a sitcom catchphrase.

The Big Bang Theory's showrunner Steven Molaro released a statement in response, on behalf of the fictional honoree. "Sheldon would be honored to know that Euglossa bazinga was inspired by him," Molaro said. "In fact, after Mothra and griffins, bees are his third-favorite flying creatures." (Bazinga!)

It's ending because of Jim Parsons

Just before CBS started airing the 12th season of The Big Bang Theory, the show's powers that be announced that the upcoming batch of episodes would be its last. Co-creator and executive producer Chuck Lorre had gathered the cast in his office on the set on August 22, 2018, where star Jim Parsons, through tears, announced that he was leaving the show at season's end. Immediately after, Lorre told the cast that everyone would be leaving at season's end, because he'd opted to end the series rather than do it without Parsons (or Sheldon). According to Deadline, Parsons told Lorre of his decision a few days before that meeting, and plenty of executives secretly (although unsuccessfully) tried to get Parsons to change his mind. The four-time Emmy winner may have even turned down as much as $50 million to stay with The Big Bang Theory for two more seasons.

Mac attack? Denied!

When The Big Bang Theory was getting off the ground in the mid-2000s, former child superstar Macaulay Culkin was in the midst of a comeback. He'd ended a long hiatus with appearances in two indie films, the religious satire Saved and the club kid murder mystery Party Monster. Big Bang Theory producers wanted very much to be in business with the former Richie Rich and Kevin McAllister. Culkin guested on The Joe Rogan Experience podcast in 2018, and confessed that "they pursued me for The Big Bang Theory. And I said no." The reason: He thought the show sounded terrible. "It was kind of like, the way the pitch was, 'All right, these two astrophysicist nerds and a pretty girl lives with them. Yoinks!' That was the pitch." Culkin didn't reveal which character he would've played, but he did add that he had to reject producers' overtures two more times. "Even my manager was like twisting my arm," Culkin added.

At last, the origins of Bazinga! revealed

Jim Parsons' occasionally sputtered utterance of "Bazinga!" is a classic TV catchphrase that ranks with the all-time great T-shirt-worthy TV expressions, such as "Cowabunga!" or "No soup for you!" It's Sheldon's preferred term of triumph for a well-executed prank on his scientist friends, such as jumping out of a ball pit, or emerging from the cushions of a couch. (Plus, it's fun to say "Bazinga!" Give it a try.) 

The phrase — and the proper time to say it — is a direct carryover from the Big Bang Theory writers room. Staff writer Stephen Engel, who wrote for the show in 2008 and 2009, loved to set up fun and innocuous practical jokes to rib the other scribes. One of his favorites: slicing up a grapefruit and then taping it back together. "I'd open it up and Stephen would say, 'Bazinga!'" co-creator and producer Bill Prady said at a 2013 PaleyFest event. "It was Stephen's word for 'gotcha.'"

The cast has some real musical chops

The Big Bang Theory just loves to insert musical sequences now and then to break up the setup-wisecrack-laughs formula, and whenever possible, they let the actors perform their own musical stunts. That works out because a number of the cast members know their way around an instrument.

In the 2013 episode "The Romance Resonance," Bernadette (Melissa Rauch) gets quarantined (for reasons both silly and complex), which leads to Howard (Simon Helberg) leading the whole Big Bang group in a performance of a special song he wrote for her (sung through a sealed window). The actual composers of the song are Kate Micucci and Riki Lindhome, of the comedy musical duo Garfunkel & Oates; both appeared on the show individually before. Helberg sang and accompanied himself on keyboards, and it only took him one take to perform the song perfectly.

Two other Big Bang actors learned to play instruments — no small feat — just for the show. Sheldon plays the theremin, an electronic instrument used to make those spooky, high-pitched noises in old science-fiction and horror movies, so Jim Parsons figured out how to operate one, too. It's a little easier to learn than the harp, which Mayim Bialik took up when writers decided Amy Farrah Fowler played the angelic stringed instrument.