Ellen Gray: Liza Lapira is playing in 'Traffic,' and she likes it

TRAFFIC LIGHT. 9:30 tonight, Channel 29.

SHE'S BEEN an agent (and a mole) on "NCIS," a neuroscientist on "Dollhouse" and an internal-affairs officer on "Dexter," but it's doubtful that any of those roles required the combination of cunning and cuddling that Liza Lapira needs on the set of Fox's new comedy "Traffic Light."

Because this time she's working with a child.

Children, actually - twin toddlers who play the son that her character, Lisa, shares with Mike (David Denman), the show's married couple.

W.C. Fields may simply have warned against it, but on a recent swing through Philadelphia, Lapira described working with kids as "both euphoric and stressful."

It's "euphoric in that they, he - Sebastian and then Tristan - are adorable, they're loves. And they run to you and they hold you and there's nothing better in the world.

"Stressful, in that when they're done, I get into mother nurturing mode, like how do I fix it? Because when they're done, and we have to still keep going, it's up to me and David" to try to coax them along, she said.

"We do our best. When the camera [operator] calls, 'Cut,' we don't put them down. We hold them, we talk to them."

The twins are "like the actual stars of 'Traffic Light,' " she said, laughing. "They are the divas. When they come to set, David and I stop everything and run to, like, greet them. They're the don."

For good reason.

"They have limited hours, they have limited temperament, like they'll only want to go in the crib a certain amount of times," she said. "But they're beautiful kids. And what are you going to do? They don't understand. They're 1. You know, they don't understand that we have to do different-sized lenses and a two-shot" in the same scene.

"They don't know they're famous, they don't know they're getting paid, they don't know what residuals are, or health insurance."

Presumably, Lapira knows all about those things, but in making the move from TV drama to comedy - and signing on as a regular from Day 1 rather than joining a show already in progress - she was, she insisted, interested mostly in the writing.

"It was not even a conscious decision in terms of which genre - I just chase where the good writing is. I thought it was funny, so I went for it," said the Queens native of "Traffic Light," which is based on an award-winning Israeli show of which she's seen only clips.

"What I hear from my bosses is it's different tonally. . . . I think it's a broader humor."

One of several current comedies about people in different stages of their relationships, the U.S. version of "Light" has Lapira and Denman in the "red light" marriage.

"It could be misconstrued as depressing," she acknowleged. "Life over. It could definitely be read that way. But I choose it to mean we've both stopped looking. We're going to stop and stay for a while. We're not in the dating scene, we're going to stop that part of our lives and enter into this new, great part of our lives."

It doesn't hurt that in a medium that too often pairs dumb men with smart women, "Traffic Light" spreads out the funny. Not to mention the dumb.

"Lisa does some dumb things, too," Lapira said, laughing. "So does Callie [Aya Cash] . . . But, yeah, the women are allowed to be funny and the women are allowed to make mistakes and the women are allowed to pine for freedom, just like the guys."

Three of Lapira's co-stars have at least a foot on her - she's 5'-2", Denman's 6'-4" and Nelson Franklin and Kris Marshall are 6'-5" and 6'-2", respectively - but, if the height difference strikes some as funny it was "by default, not by design," she said.

"As a matter of fact, David Denman, the generous, generous actor and scene partner that he is, pretended to be shorter than me during the audition test," Lapira said. "Meaning he did such a good job of subtly hunching over to be eye level with me that I didn't realize he was 6'-4" until we started shooting. And even then he had to tell me.

"Now he gets to stand up straight and I either stand on something or we just are what we are," she said.

The actress, whose ancestry is "Filipino, Spanish and Chinese," claims some tall relatives - "I have a female cousin who's 6 foot, so it happens" - but she isn't responsible, she said, for the listing on IMDB.com that puts her at 5'-5".

"I'm proud. I represent the petite women of America. That's fine."

CBS yesterday announced that it had renewed "How I Met Your Mother" for two more seasons, taking it through 2012-13, by which time star Josh Radnor might actually start to look like Bob Saget, who voices his character's future self. . . . TV's worked out for Jennifer Lopez, and now her Grammy-winning husband, Marc Anthony, is joining TNT's "Hawthorne" as a regular. *

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