'Big Bang Theory' Series Finale: 7 Secrets to Know Before Watching the Last Episode! (Exclusive)

Grab some Chinese food, invite your friends over and snag 'your spot' on the couch – we're just days away from the series finale!

Grab some Chinese food, invite your friends over and snag "your spot" on the couch because the series finale of The Big Bang Theory is almost here!

The long-running CBS comedy is officially coming to a close on Thursday with a special two-episode event and it's shaping up to be a finale that fans will never forget.

But if you're already quietly singing "Soft Kitty" to yourself because you're sad to see it go, well then, we've got something that will make you happier than Sheldon at Legoland...

ET has gathered up seven exclusive secrets you need to know before tuning into Big Bang's last goodbye!

1. Why End It Now? After 12 seasons -- often as TV’s number-one comedy -- and with multimillion-dollar salaries, you might be wondering why the cast of The Big Bang Theory would want to say goodbye to this geektastic show.

Turns out, it was Emmy Award-winning actor Jim Parsons who decided that the time was right to close the doors on Sheldon and Leonard’s Pasadena apartments. “I had just turned 46 and I don’t know. It just seemed like the right time in life to go, OK, what’s next?” Parsons explained while sitting down with ET’s Kevin Frazier on set in April.

Ken Hively/Los Angeles Times via Getty Images

2. The Finale Scripts Were Top Secret: While the Big Bang executive producers didn’t reach full-on Game of Thrones level of secrecy, they did admit that they took extra levels of precaution in order to prevent leaks.

“I mean, there’s only so much you can do because we’re still putting it up in front of an audience, but we went to extra care with the scripts,” showrunner Steve Holland explained to ET over the phone last week. “We did a smaller distribution of the scripts, we watermarked all the scripts with people's names, so if they got leaked, we knew who to track down.”

3. Each Character Gets Time to Shine: With such a big cast, the executive producers wanted to make sure that every member of our geek-chic group had an ending that fans would be pleased with. “We really have always felt that it was an ensemble show, so we wanted to make sure that everyone kind of had their moment to shine in the finale,” Holland revealed.

“We just did our best to end the series in a way that honored these characters that we've loved for 12 years,” executive producer Steve Molaro added. “I would say the final two scenes are what we are most excited about for people to see. We’re really proud of it.”


4. The Two-Part Episode Has Tons of Easter Eggs: The one-hour finale is jam-packed with inside jokes, on-set secrets and never-before-seen moments that only true Big Bang fans will notice -- including a sparkly return and an emotional math problem. Luckily for you, ET will be breaking down all of the Easter eggs in a special article after the episode!

5. There’s a Surprise Scene at the End:  For the friends, family, fans and press members who were lucky enough to score an invite to The Big Bang Theory’s final live audience taping, they thought they were getting to see the entire episode. They thought wrong.

The showrunners dished to ET that they pulled one last “Bazinga!” and there’s actually a bonus scene at the very end of the episode. “There is a final scene that even the audience in the studio did not get to see,” Molaro revealed. “Now you get to see how it really all ends.”


6. And a Shocking Celeb Cameo! That’s right – The Big Bang Theory has had some truly sensational guest stars over the past 12 seasons, but they’ve never had this beloved celeb on the series before. We’re not going to dish too much more on this secret, but we will say this: ET will have the full story explaining how the executive producers convinced this star into doing a cameo!

7. Spinoff Talks Are Happening: If you’re still not quite ready to say goodbye to the show, take comfort in the fact that TV showrunner extraordinaire Chuck Lorre has already been brainstorming about how the series could get another spinoff. “It certainly has been discussed. A lot,” the creator dished to ET’s Nischelle Turner at the Big Bang wrap party.

And it sounds like one major star from the series could be convinced to continue the story! “If Chuck came and said, ‘Let’s do it!’ I’d say yes,” leading lady Kaley Cuoco admitted. “Other than that, I don’t see a spinoff for myself, but I don’t like to say no to Chuck. So if he wanted that, I’m in!”

The Big Bang Theory's series finale airs May 16 at 8 p.m. ET/PT on CBS, and Thursday's episode of ET -- featuring tons of exclusive content -- will be broadcast from the set of the sitcom. Check your local listings!