Through it all, the core group have remained close friends not just on-camera but off as well.

And after working together for a dozen years, they have more than a few stories to share.

From first impressions to spin-off talk (NCIS: Raj, anyone?

“The Rhinitis Revelation” – Coverage of CBS' THE BIG BANG THEORY scheduled to air on the CBS Television Network. Photo: SONJA FLEMMING/CBS ©2011 CBS BROADCASTING INC. All Rights Reserved.

), they reveal all.

He was very quiet and had a BlackBerry in his hand, playing with it.

I just got it."

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He was very cute how he said it.

I thought he could totally play Sheldon.

Charming and innocent.JIM PARSONS:I already knew who Johnny was fromRoseanne.

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That was weird because I don’t think I’ve ever auditioned alongside someone I had seen act before.

He knew what he was doing and was doing it in a strong way.

I didn’t feel like he needed my help.

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I didn’t feel like he was bleeding into my work.

He was his own distinct thing.JOHNNY GALECKI:We all thought Kaley was the coolest person in the cast.

As soon as we were done with rehearsals or the live audience, she was like taillights.

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We all assumed she had much better social plans than we did.

No, really, I didn’t know Simon Helberg at all when I signed up.

I had recently seen Mayim on her episode ofWhat Not to Wearon TLC.

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They had dressed her.

It was some of her best work.GALECKI:Obviously it didn’t take.PARSONS:I know.

That’s the first thing I did after 12 years away.

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Simon, what did you think of Melissa?HELBERG:Am I allowed to swear?

[He looks at Rauch] It almost seems like you played a different character.

You were very different.MELISSA RAUCH:I was super-religious.

There had been many women in Howard’s life, but I knew it was special because we clicked.

I wish he was still like 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.

You just beelined out of here.

We used to hang out afterward.

Then you finally came and said, “I don’t have any friends.

Can I hang out with you?

There were Ping-Pong tournaments.

Where were we?NAYYAR:San Ysidro Ranch.HELBERG:Now we just go on vacation with your parents.

How were you that first season?

Were you unfailingly polite to one another?HELBERG:The writers' strike was then.

It was 100 days.

I went to dinner almost every night with Jim.

It wasn’t a plan.

We lived 10 minutes from each other.

We kept thinking they were going to call us back to work.

Let’s just go have Mexican food.

We’ll get that call.

I gained 200 lbs.

from the mole.GALECKI:Oh, the mole!

That reminds me of Mexico City.

I really thought they were trying to be nice by saying, “Oh, you are the No.

1 show in Mexico.”

We hadn’t experienced that before, the rush of people and photographers.

The next day we were on the cover of the paper.HELBERG:I remember it said “nerdo.”

I don’t speak Spanish, but I’m pretty sure [I know] what it meant.

Was the show misunderstood at first?

It was just the name.

They were like, “Oh, what is this show?

“GALECKI:I remember them likening us toThree’s Company.

First of all, your math is off.

And based on what?

That Kaley is blonde?

It went from those absurd similarities to the newFriends.

Oh, that was quick!

But we’ll take it.

Is that cool?HELBERG:If there’s anything cool about an obit .

.PARSONS:They can be really well-written sometimes.HELBERG:They can be.

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.PARSONS:Whatever ends up happening to us, this is life-altering.

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.

We didn’t wake up in season 3 and think this show is going on forever.

We’ve never spoken that way.

I remember you saying, “I don’t know, maybe?

It’s hard to say.”

And I remember Kunal saying, [imitating his voice] “Oh yes, absolutely.”

I asked him how many pilots he’s done.

[He looks at Nayyar] It’s the last time you were right about anything.

Warner Bros. just doesn’t have enough money.

Why couldn’t there be a spin-off likePenny Loves Leonard?

AmyorNCIS: Raj?CUOCO:There will probably be anNCIS: Raj.

Like 10 of them.

OrJust Raj.NAYYAR:I’ll be right back!

I have to make a phone call.PARSONS:That’s a very good idea.

What do you do?

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?CUOCO:They might be killing us all off.

We don’t know what happens in the finale.BIALIK:That’s the answer to your question.

We can’t do a spin-off because we all die.HELBERG:They don’t see us die.

We get into the elevator, and then the cables snap.

It cuts to Chuck’s vanity card.

You hear an explosion.

We all ended with a big bang!

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