What the remarkable run of ‘Big Bang Theory’ means for Hollywood — and the show’s cast and crew

There’s the Big Bang Theory in science that explains how the universe began from a staggeringly hot, dense point roughly 13.7 billion years ago. But millions are more familiar with the other “Big Bang Theory”—the one that’s been on CBS for 11 years. And in the cosmos of modern-day television, it stands out like a shining star.

True, this multi-camera series is not the most buzzed-about comedy on the small screen and its broad, safe humor doesn’t exactly make it a sparkplug in the critical think-piece culture. And, yes, its awards success may lag far behind other comedies such as “Modern Family” or “Veep.”

But against all odds, “The Big Bang Theory” has established itself as one of the pillars of the prime-time scene. It’s one of CBS’ most reliable hits — the Thursday show is currently averaging 14 million total viewers (a number that rises to nearly 19 million when delayed viewing over a week is factored in), making it a force on one of television’s most popular nights. It’s launched a successful spinoff, made millionaires out of its previously little-known cast, employed hundreds of actors and crew members and served as a potent springboard for other new CBS comedies.

“We’ve made more than 250 episodes,” said veteran TV producer Chuck Lorre, who co-created the show with Bill Prady. “We didn’t expect this, you know? We just wanted to make a show about extraordinary minds.”

It’s the kind of long-running mainstream broadcast show that pours hundreds of millions of dollars into the local economy. The show’s steadfast heights are a rare achievement at a time of declining ratings and this gluttonous age of TV that, quite frankly, could benefit from a scientific formula to help viewers get a handle on all the TV shows vying for their attention. It remains one of the top 10 most watched shows in the country, with far more viewers than even the most popular streaming and cable series.

And it has accomplished this largely without resorting to stunts, gimmicks, or flashy guest stars while continuing to mine gold out of its premise and no-frills formula of young genius grappling with the fast-evolving real world. A fact that is not lost on executive producer Steven Molaro, who served as a longtime showrunner on the series until last year when he left to shepherd the comedy’s prequel spinoff, “Young Sheldon.”

“There’s so many TV shows out there — so many,” Molaro said. “I get it. It’s always exciting to be like, ‘Oh, this is something new and buzzy that people are talking about, I wanna see that.’ But that people still care enough about these characters after 11 years — they don’t care that it’s broad, they don’t care that it’s multi-camera, it’s so crazy and gratifying.”

The show’s longevity has helped maintain the sitcom’s status as a valued property for CBS and Warner Bros. Television, which produces the series.

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“The value is incalculable,” said Kelly Kahl, the president of CBS Entertainment who had been the head of scheduling when “The Big Bang Theory” launched. “Every scheduler, every network president, anybody who works at a network, you live for a show like this. The interesting thing to me is it’s as dominant as it’s ever been.”

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In addition to contributing for years to CBS’ standing as the most-watched network, the show’s enviable ratings have made it a key profit-maker for the broadcaster — the series alone brought in $125 million-$150 million in ad revenue per season for CBS. And its syndication revenue has reportedly generated more than $1 billion for Warner Bros. Television.

“The financial reward has been extraordinary,” said Peter Roth, the president and chief content officer of Warner Bros.Television. “But as importantly, it’s a defining series for our studio. We are only as good as the product we make, when you have a show that resonates globally as much as this series does, it’s a source of tremendous pride.”

Quite the evolution when you consider the show, which launched in 2007 on the precipice of television’s modernization, ranked No. 68 in its first season.

Conceived by Prady and Lorre, who was riding high on the success of “Two and a Half Men,” “The Big Bang Theory” was inspired by the personalities Prady encountered during his pre-Hollywood career as a computer programmer.

The original pilot was developed for the 2006-07 television season and featured the characters Leonard and Sheldon — played by Johnny Galecki and Jim Parsons, respectively — who were socially challenged physicists working at Caltech. The original female lead was a street-smart character, Katie, played by Amanda Walsh.

When the pilot didn’t get picked up, Lorre and Prady retooled it. Katie became Penny, an across-the-hall neighbor who is a waitress with Hollywood ambitions (with a less-manipulative demeanor), played by Kaley Cuoco. And friends were added: aerospace engineer Howard Wolowitz, played by Simon Helberg, and astrophysicist Raj Koothrappali, played by Kunal Nayyar.

The overhaul got the pilot picked up. The show premiered in the fall of 2007, to so-so ratings. Its fate grew grim when just half of its initial 13-episode order aired before the 2007-08 Writers Guild strike halted production and brought Hollywood to a standstill.

“My biggest concern was, I was on a TV show and I had just bought a new car,” Nayyar recalls. “I had bought an Audi and I was like, oh my God, I have to make the payments on my Audi. I called my dad and was like, Dad, I don’t know If I can afford this if we don’t come back to work.”

Galecki, too, recalled the anxiety: “We left the stage when that writers strike hit, very depressed. It felt like we hadn’t gotten a foothold. We didn’t think we had enough time for word of mouth to catch on.”

But it did. Instead of becoming a casualty, “The Big Bang Theory” thrived, steadily building an audience who caught up on the reruns CBS ran during the strike — the luck of a pre-Netflix era.

“At some point you read the numbers and you can kind of read the audience’s passion,” Kahl said. “That’s something we saw over the strike, the repeats were doing almost as well as the originals. That’s something that, as a scheduler, tells you something’s happening and that people are discovering the show.”

The show continued on an upward trajectory from there, eventually reaching a point where it was earning multiple season renewals. American viewers were fully geeking out over the series — undeterred by its smarty-pants leads and references to the Doppler effect and projectile motion.

“It just got bigger and bigger,” Helberg said. “For the first six or seven years, it was like every episode was bigger than the last.”

Further proof of its power came in its fourth season when, after airing Monday nights its first three years, CBS made the bold decision to move the comedy to the competitive 8 p.m. slot on Thursdays — where the comedy proved itself as a mighty competitor to “American Idol.” Not long after, in 2011, the show entered syndication, with heavy repeats on local broadcast stations and cable’s TBS fueling the fandom by introducing the series to new viewers.

All this from a multi-camera sitcom, a format whose obituary has been written many times, on a broadcast network.

On a recent Tuesday on Stage 25 on the Warner Bros. lot in Burbank, taping of the show’s milestone 250th episode is underway. Lorre and Prady are in the wings observing as the 200-plus audience members, which includes Cuoco’s dad (a regular visitor each week), laugh it up while a back-and-forth unfolds in Sheldon and Amy’s apartment about the origins of the sandwich during the gang’s regular Friday night gathering for Chinese takeout. A simple windup, sure, but that’s part of the charm, the cast and producers say.

“We are a broadcast show and I think doing this show and seeing the response it’s gotten has brought meaning to that word for me in a way that I never understood before,” said Parsons, the series’ biggest breakout star. “The goal here is to attract as broad an audience as possible and there’s a cynical way of looking at that, which is, ‘Well, of course you do, it’s a business model and you want the most money.’ Well, sure, but I think the more pure way of looking at something like this is that as an artist, as a creator, as a performer, as an entertainer, it’s not an uncommon thing to want to entertain as many people as possible.”

Though Parsons has become a four-time Emmy winner for his role as Sheldon, the sitcom hasn’t been much of an awards-show magnet.

“I don’t think the show gets enough credit — and I mean that in the sense of the writers don’t,” Cuoco said. “I don’t think people understand having to write something funny 24 weeks out of the year is so unbelievably difficult. It’s almost impossible to keep something this funny up for so long.”

Keeping viewers engaged to the levels “The Big Bang Theory” commands over a long haul is no easy task. The producers behind “The Big Bang Theory,” admit it’s a challenge to come up with real, relatable and funny stories. But not impossible. Allowing for character development, which comes at molasses pace for this group of social misfits, and introducing new characters to expand the world has been key.

“You want these characters to grow and change,” said Steve Holland, a longtime executive producer and writer on the series who, this year, became its showrunner. “But you don’t want to lose who they are.”

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Two female characters were added as series regulars in the show’s fourth season. Microbiologist Bernadette Rostenkowski, played by Melissa Rauch, became a love interest for wannabe womanizer Howard — they eventually got married and, this season, are expecting another child. And neurobiologist Amy Farrah Fowler, played by Mayim Bialik, through her relationship with Sheldon, became an opportunity to explore two socially awkward people developing a relationship and learning to be vulnerable — they’ve had sex and took things to the next level by moving in together.

Molaro pointed to the decision to have Sheldon and Amy move in together as a development that resulted in a lot of debate.

“We thought a lot about — is that a good idea? Is that a bad idea? If Sheldon is not in the apartment,” Molaro said, “did we break the show? It’s a lot of those moments and trying to find what feels real and right.”

Holland added: “And it opened up a whole new world of stories and growth for the characters.”

“It’s such a simple thing,” Molaro continued, “He moves 50 feet away and it gave birth to 100 stories.”

Now, this week’s season finale on Thursday will feature the wedding of Sheldon and Amy — in what would seem to be a logical winding down of the series.

So how much bang is left in the series — especially since, after so many years on the air, its production price tag has escalated with producer fees and cast salaries. (The five main actors who have been with the series since its beginnings — Parsons, Galecki, Cuoco, Nayyar and Helberg — make just under $1 million an episode.) The show has already been renewed for a 12th season, but CBS and Warner Bros. Television have not yet announced plans to keep the show going beyond that.

“Obviously it will be dependent on the actors, the network’s need for it,” Roth said. “I believe that everyone will be happy to have it continue as long as possible, but I think the actors will have to determine whether or not they want to continue.”

In an industry where sustainability is the the hardest act to pull off, the sitcom’s longevity — as Nayyar puts it, “Kids who were born 11 years ago are now watching the show” — has made it a dependable employer. The series has a crew of roughly 150 on set—but scores more work on the total production. (In 2016, according to FilmLA, there were about 150,000 direct jobs in film and television in Los Angeles County, largely driven by television. Those jobs totaled about $14 billion in wages in the county).

Mark Cendrowski, who directs most of the episodes of the sitcom, says finding stability in the unpredictable entertainment industry has been a windfall.

“I’ve been on shows throughout my career that get canceled the week before Christmas,” Cendrowski said. “And I’ve been out of work at times waiting because when a show gets canceled, other shows have already been staffed and you have to wait until something else comes along. That’s an anxiety-filled time. But here, we don’t have that. We know we’re coming back. And it makes life easier.”

With likely more seasons behind it than ahead, though, it’s only natural to think of the looming end.

“I look at the end of the show much like I think a devout Christian looks at death — not afraid but hopeful to see the thing that they believe in,” Parsons said. “I know whenever the day comes I will be very emotional about it. It will be the natural death of something wonderful. Even though it’s not a tragedy, it’s one of those things where you’re still going to be, I would think, very moved to see the end of an era of your own life.”

yvonne.villarreal@latimes.com

Twitter: @villarrealy