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?” 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. The show is also a smash globally, with Canada, the UK and Brazil delivering some of its biggest ratings success stories. The 32-year-old Helberg, who has a one-year-old daughter with actress-wife Jocelyn Towne, said he sees a long life for “Big Bang.” — AP