New On CBS Primetime, 'The Big Bang Theory' Season 9

It's the moment so many have waited for on "The Big Bang Theory," the wedding between Leonard and Penny.

"I think they were ready to take the plunge at that point. Enough talk let's do this, and I think the audience was ready for that too," said Johnny Galecki about Leonard and Penny's decision to elope at the end of last season.

Season 9 will begin in Las Vegas for the big day between the two, but some cast members didn't believe it would ever happen.

"I didn't know anything about Leonard and Penny getting married and I thought for sure something would be derailed between season 8 and season 9 and low and behold they went and got married," said Mayim Bialik who plays Amy.  "I kept waiting to find out that they weren't going to but they went ahead and did it."

On the other hand Sheldon and Amy have broken up after five long years of dating, leaving Sheldon sad and confused.

"Sheldon and Amy [don't] have much going on," said Jim Parsons who plays Sheldon. "I don't think he understands why they are apart… but he also wants to be back together because he wants what he wants."

"The Big Bang Theory" returns for it's ninth season Monday, Sept. 21 (8:00-8:30 PM, ET/PT). The show will move to its regular time period Thursdays, (8:00-8:30 PM, ET/PT) on Nov. 5, after Thursday Night Football.

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