Oftentimes, Cheryl Hines has no idea what is going on, nor does she know whether something is funny or not. This has benefited her greatly in her portrayal as Larry David’s wife on HBO’s wickedly funny improvisational comedy, “Curb Your Enthusiasm.”

“The big joke on the set is that I’m always the last to know anything,” says Hines. “I’m always in the makeup chair, asking the artists if they know anything about the scene we’re doing. All I hear is, ‘We’re rolling!’ Nobody wants to tell me anything. I ask Larry and he says, ‘Oh, you’ll figure it out.’ Sometimes that’s all I get!”

She also doesn’t get applause. “Everything in my experience had been before a live audience,” she says. “You know immediately if something is funny because people laugh. This is different. There is no audience, no gauge as to what is funny, except from Larry and the other producers. At the same time, you can take bigger risks that way.”

The uncertainty of an unscripted high-profile comedy series might dissuade a less experienced talent, but Hines is uniquely qualified, having trained with the famed Groundlings for years. (Her first teacher was Lisa Kudrow.) From there, Hines paid her dues and climbed the Groundlings’ company ladder. One night Robert Weide, one of the “Curb” producers, discovered her at a comedy showcase while he and David were searching for an actress to play David’s wife in the original one-hour HBO special that spawned the series.

She remembers her “Curb” audition. “I had no idea what I was doing until I got into the room,” she says. “Larry said, ‘We’re married. Let’s just try something.'”

Luckily, they’re still at it.