The Big Bang Theory The Big Bang Theory

The morning after he won the Emmy for best lead actor in a comedy series, Jim Parsons thought he might have dreamt the whole thing. But his cell phone's constant buzzing was confirmation that his portrayal of physicist Sheldon Cooper on The Big Bang Theory had made him a bona fide star. "I have been absolutely inundated with texts, calls and e-mails from so many people," Parsons told TV Guide Magazine just hours after taking home the trophy. "I have several texts that I cannot identify. Somebody named Kimberly has written me and I don't know if I should just write back and say 'Kimberly who?' You don't realize how many people there are in your life until something like this happens and you're like, holy moley, I have a lot of people in my life that I love."

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There are a lot of people who love Parsons, Sheldon and Big Bang, the CBS sitcom about an endearingly idiosyncratic group of scientist friends and their aspiring-actress neighbor. Season 4 presents the show's biggest challenge yet: a move to Thursdays at 8pm, a time slot that's been home to TV classics like The Cosby Show, The Simpsons and Friends.

The season begins with an unexpected turn of events: The emotionally stifled Sheldon will embark on his first romantic relationship — of sorts. Mayim Bialik returns in her recurring role as Amy Farrah Fowler, the brilliant but quirky woman whom Howard (Simon Helberg) and Raj (Kunal Nayyar) secretly set up with Sheldon via an online dating service in last May's finale. "They are pursuing a really odd relationship. It's very much one of the mind," says exec producer Bill Prady. Amy has a Ph.D. in neuroscience, as does Bialik, the star of '90s sitcom Blossom, who earned her degree from UCLA in 2007. "Sheldon insists Amy is not his girlfriend, although they are discussing reproducing because they believe their offspring have the potential to be the first in a series of benign overlords to lead humanity to a brighter tomorrow," adds Prady. "They believe they may owe it to humanity."

Could it really be that Sheldon, a man so socially handicapped that he once needed to create a "friendship algorithm," can handle romance? "We do go on a quote-unquote date, but as you would suspect with a Sheldon relationship, it's not at all by the book," says Parsons. "He's very literal, as usual, about it. This is not a girlfriend. This is a girl who is a friend. As far as having a relationship, it's in the most literal sense: They're relating, especially through text messaging. That seems to be their best way to deal with each other." While it's likely the relationship will be played for laughs, Parsons cautions not to count Sheldon out: "I think he could be in a real position to be surprised by his own emotions."

He'll have to carry the romantic torch in the wake of last season's breakup between charmingly insecure Leonard (Johnny Galecki) and bubbly Penny (Kaley Cuoco), who now must try to stay friends without benefits. "They're going to have to deal with what's going on in each others' lives, and that's going to get a little complicated for them," Prady says.

Some fans objected to the consummation of the beauty-and-the-geek romance so early in the life of a series that's clearly set for a long run. But Galecki is glad the writers took a chance. "When everybody in the room approves of something, that means you are doing something very safe," he says. "That disagreement in the audience always excited me."

Both actors are happy with how the story has played out so far. "I thought it was very near to real life," Cuoco says of the relationship, which Penny ended after Leonard's use of the "L" word apparently kicked her commitment issues into overdrive. "I like that we didn't wait till the last day of Season 9 for them to get together. I'm sure they are going to dabble in this relationship much more in the future." Galecki agrees. "I'm hard-pressed to believe that that'll be the end of it," he says. "We see too many glimpses of true caring between them. What we don't see, and what they don't possess, are the tools to know what to do with that caring. Hopefully we'll be given enough time to watch them learn."

For more with The Big Bang Theory cast, including scoop on a love interest for Howard, pick up this week's issue of TV Guide Magazine, on newsstands Thursday, Sept. 16!

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