On the Set: The Secret Behind The Big Bang Theory's Comic Chemistry

It's Luau Day on the set of The Big Bang Theory, with the crew adorned in Hawaiian flower-print shirts and the craft services table boasting a massive spread of island eats. Johnny Galecki, who plays Leonard, gets into the spirit as he ambles through a small patch of grass just outside the door of Stage 25 on Warner Bros.' Burbank lot, softly strumming a ukulele ("I keep it around the set," he says with a smile) as he waits for his next scene. Even though they're only 24 hours away from taping an episode featuring special guest star Bob Newhart, it's just another day at the beach for the cast and crew of television's No. 1 comedy.

"We love this show and, even more personally, I love going to work," says cocreator Chuck Lorre. "I genuinely laugh my ass off when I watch this stuff, and every member of this cast will routinely blow my mind and make something magical happen."

That magic is undoubtedly in the air because, in its sixth year, Big Bang is bigger than ever. So far this season, the show has pulled in an average of 18.5 million total viewers per week, making it the No. 2 scripted series on television, behind only the CBS drama NCIS. And on January 10, the Star Trek-centric "Bakersfield Expedition" episode was the first to crack 20 million total viewers, the highest rated half hour in the show's history. "When I hear those numbers, it feels like it's happening to someone else, even though it's happening to us," says Kunal Nayyar, who plays Raj. "It's hard to wrap your brain around it because it feels to us on set that things haven't changed. We're the same people and we still work as hard to make the show as good, if not better, over the years."

And it's not just original episodes. On April 18, a repeat beat the once mighty American Idol's live ­results show in the 18-49 demographic, while six-nights-a-week reruns on TBS frequently outdraw original network programming.

A major contributing factor to this year's record-breaking ratings is a creative resurgence spearheaded by new showrunner Steve Molaro. What used to be a series about socially incompetent geniuses has evolved into a touching exploration of the platonic and romantic relationships between seven best friends. "I don't remember the last time Jim [Parsons, who plays Sheldon] or I had one of those long, brain-wrenching, scientific-jargon speeches," Galecki says. "It's not about that anymore; it's about how they relate to one ­another, as opposed to how they ­relate to science."

"We've been having a really strong year creatively, and the show taps into a thing that seems to resonate with people who feel alienated," Molaro says. "That's at the core of the show, and even people whom you would consider popular can ­relate to that."

Season 6 featured several big, emotional moments, including Penny (Kaley Cuoco) telling Leonard she loved him; the blossoming semi-­intimacy between Sheldon and Amy (Mayim Bialik); and the ­often hilarious growing pains of newlyweds Howard (Simon Helberg) and Bernadette (Melissa Rauch). Even Raj began to get over his fear of women, dating Lucy (Kate Micucci), a web designer with geeky interests similar to his. "It's ­always exciting to go deeper [into these characters] because it's something new, but all of us here still manage to keep it funny," says Helberg. "My character is 180 degrees different than he was just two seasons ago, but it's all baby steps. It took five seasons for Sheldon to hold Amy's hand and for Howard to get married, so it doesn't come from the urge to be flashy. It's really earned."

Molaro is mum when it comes to revealing the plotlines he's planning for Season 7, but the actors have their own wish lists. "I really don't want to work at the Cheesecake Factory," Cuoco admits. "I just think it would be so funny if Penny ­became a successful actress." And there are still more family members to introduce, like Howard's father ("At a certain point, when it feels right, that would be ­exciting," says Helberg) and one of Sheldon's most talked-about relatives: "I think we will meet Meemaw one day," Parsons says. "Maybe the buildup's too much, but I don't think so. We need to see her."

Big Bang's momentum shows no signs of slowing down any time soon. And the presence of a sitcom legend such as Newhart brings an ­indescribable energy to the show that resonates with Parsons, a longtime fan who still catches repeats of The Bob Newhart Show on MeTV. "There's something about watching those reruns and being able to get perspective on it," Parsons says. "That is classic television — you know because here we are watching it still. It gives me a feeling of rejuvenation walking back on our set after having watched it, and the hope is that maybe you're a part of history, too."

For more with The Big Bang Theory and to see our list of the 60 Greatest Comedies of All Time, pick up this week's issue of TV Guide Magazine, on newsstands Thursday, May 16!

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