The Big Bang Theory finale: See exclusive behind-the-scenes photos

01 of 18

The final table read

The Big Bang Theory BTSCR: Joe Pugliese/CBS — Joe Pugliese/CBS

The Big Bang Theory has come a long way from that original pilot in 2007, which critics responded with mixed reviews. "I remember them likening us to Three's Company," recalls Johnny Galecki. "First of all, your math is off. And based on what? That Kaley is blonde? It went from those absurd similarities to the new Friends. Oh, that was quick! But we'll take it."

02 of 18

International stars

Jim Parsons remembers the first international publicity tour they took in Mexico. "It was for publicity for Warner Bros. I really thought they were trying to be nice by saying, 'oh, you are the No. 1 show in Mexico.' But when we got to the plane and into the airport, it was a little bit like the Beatles had arrived. We hadn't experienced that before, the rush of people and photographers. Then we got into the van for the long trip to our hotel, and there were these huge billboards, and sure enough they said, 'Numero uno sitcom!' The next day we were on the cover of the paper."

03 of 18

Life-changing

"Whatever ends up happening to us, this is life-altering," says Parsons. "You may be part of something else that is as life-altering as this, but that's a high bar to hurdle."

04 of 18

Taking care

"We all care so much," says Kunal Nayyar (Raj). "We want to get it right."

05 of 18

Frankly speaking

"It will never be fully eclipsed," says Galecki. "We will always be associated with one another. It's such an incredibly unique experience that only the seven of us can really understand having. You can talk about the cast of Friends, but this is different in its own way. There is no one else but this circle of seven that can even pretend to relate."

06 of 18

Tears of joy

"We never expected any of this to happen," says Kaley Cuoco (Penny). "We didn't wake up in season 3 and think this show is going on forever. We've never spoken that way. Even when we renegotiate and get new seasons, we can never believe it."

07 of 18

Massive impact

"Of all the things fans say to me, the most repetitive one is, 'Your show got me through chemo or the hospital or maybe it's just food poisoning,'" says Parsons. "That is the most common thread of fan comments. To your point of not putting too much importance on it, I don't think any of us do by nature. It's our job. We love it. We are grateful for it. But it's impossible to put your feet in the shoes of someone who is really in love with it, who is using it to get through something in life. It's just too profound."

08 of 18

Love, Bernadette

"The thing I remember most is our dinner scene, and I did magic in the car," remembers Simon Helberg about one of his early seasons with Melissa Rauch. "There had been many women in Howard's life, but I knew it was special because we clicked. I had a real strong sense she'd be back."

09 of 18

How far they've come

"Jim and I had a different frame of reference when we started," recalls Galecki. "Not necessarily better by any means, because we had done a pilot for the show beforehand, and so when I met Kunal and Simon and Kaley, when we did that first table read, I'll never forget that. It felt like a band you had been playing with for years. It felt very rhythmic, very musical. Comedy always is, I suppose. I remember Kunal doing something I hadn't predicted at the table read. It changed just by a minute degree. But it just worked better. That seemed to be the case with everybody around the table. Then Kunal asked to borrow money. I thought that was odd. I only remember that because he hasn't paid me back."

10 of 18

Hitmaker

Executive producer Chuck Lorre claps the board one last time on the final night of taping.

11 of 18

Well done

As a long-running joke, the cast and crew typically boo director Mark Cendrowski when his name is announced at each taping. But not during this final week: everyone stood and clapped for the man, which brought tears to his eyes.

12 of 18

No spin-offs, please

"I've had weird dreams about a single-camera version of Big Bang," admits Galecki. "What do you do? Whose character? These characters are so a part of each other's lives! Even a spin-off with two, you'd be like, what happened to the other five? Did they all die in the elevator?"

13 of 18

Gold medalist

Embargoed 05/15/19 9pm ETThe Big Bang Theory BTSCR: Joe Pugliese/CBS — Joe Pugliese/CBS

A slipper-wearing Mayim Bialik is spotted in between takes for the series finale. Yes, she's wearing that tiara!

14 of 18

Home away from home

The cast will always have a special place in their heart for all the people who came to their tapings, week in and week out. "These audiences are insane," Cuoco recalls. "Their energy is high. I don't know how it works [to get them here]. It's like Hunger Games. They wait a long time to come. I'll read comments on my social, and I'll come across one that says, 'I have tickets for a 2019 episode.' They've had them for years. I don't think there will be anything like a Big Bang audience taping ever again."

15 of 18

Prized moment

Rauch, Bialik, Helberg, Parsons, and Cuoco take a break before shooting the final scene of the series finale.

16 of 18

Saying goodbye

"We never expected any of this to happen," says Cuoco of the show's remarkable run. "We didn't wake up in season 3 and think this show is going on forever. We've never spoken that way. Even when we renegotiate and get new seasons, we can never believe it."

17 of 18

Showstopper

"We love it. We are grateful for it," Parsons says of the sitcom. "But it's impossible to put your feet in the shoes of someone who is really in love with it, who is using it to get through something in life. It's just too profound."

18 of 18

Love, Penny and Leonard

"I'm going to owe all of my career to this show," Cuoco says. "No matter what I do after this. This is what made us who we are. We were here for 12 years. This is a big part of our career."