LOS ANGELES -- Listening to actor Simon Helberg talk about "The Big Bang Theory," you'd think his show was actually a nerdy nighttime soap. The actor, who plays aerospace engineer Howard Wolowitz on the CBS sitcom, dropped a few hints about what to expect from Thursday night's season finale.
"This time, the adventure is for Leonard," Helberg revealed, referring to the experimental physicist played by Johnny Galecki. "Howard finds Stephen Hawking's crew is sending out an expedition to the North Sea, and he gets Leonard a job, going on a boat for four months."
But there's no easy scientific equation that can tell Leonard how to choose between the expedition and his street-smart girlfriend Penny, played by Kaley Cuoco.
"The obstacle is Penny and Leonard have never been better," Helberg continued. "So, is he really going to leave her for four months?"
And Penny isn't the only one who doesn't want to see Leonard go. His roommate, the perennially neurotic theoretical physicist Sheldon, played by Jim Parsons, doesn't want to be left alone.
There's also trouble for romance-challenged astrophysicist Raj, played by Kunal Nayyar, and his new love interest Lucy, played by Kate Micucci. Raj wants more from the relationship than Lucy may be able to give -- a major leap considering she has a habit of crawling out of restaurant bathroom windows on their dates.
To add to the nerd drama, there are science jealousies at play, too.
"Howard's a little competitive now that Leonard is getting the spotlight, (because) no one cared about Howard being an astronaut. So, it creates this sort of ripple effect."
In six seasons, "Big Bang" has more than doubled its debut-audience U.S. viewership, delivering its most-watched first-run episode ever this year, with more than 20 million tuning in. Add to that number, the millions who watch the show's reruns daily on local stations and on cable network TBS. The show is also a smash globally, with Canada, the U.K. and Brazil delivering some of its biggest ratings success stories.
The 32-year-old Helberg, who has a 1-year-old daughter with actress-wife Jocelyn Towne, said he sees a long life for "Big Bang."
"I think we're all having a good time," he explained." And I think the show is far from being stale. It is kind of constantly -- not reinventing itself -- but just expanding on these characters. So, yeah, I think we're going strong for now, as long as people keep inviting us in."
The season-six finale of "The Big Bang Theory" airs at 7 p.m. Thursday night on CBS.