French Stewart says he didn't get too worked up sharing a passionate kiss with sexy co-star

Karina Lombard in Murder at the Cannes Film Festival, the new E! original movie debuting Sunday at 9 pm. After all, what's an actor to do when his wife and scores of stage hands are standing on the sidelines?

"I always thought it was sort of disingenuous when you would hear actors saying, 'Oh, well, it's very technical and there are a lot of things going on,'" the 3rd Rock From the Sun star tells TV Guide Online. "But it's actually kinda true. You're trying to make sure your head is in the right place and that she's getting some light, and meanwhile, there are 60 people there watching you. And my wife [fellow thesp Katherine LaNasa] was right there, policing all the activity."

LaNasa wasn't spying on her hubby, however. The actress — who stars in the NBC midseason sitcom These Women — has a small role in the quirky E! pic, which features Stewart as a former TV detective who gets involved in a real murder mystery.

"It's like some weird old Columbo movie," says Stewart. "I kind of like the throwback to that old '70s movie-of-the-week style. I used to sit on the end of my mother's bed back home and we'd watch Columbo and McCloud and that sort of thing."

Working on the cable flick also gave Stewart the chance to visit France for the first time, and he was not disappointed. "They just seem to know what they're doing over there," he says. "You could walk into a refrigerator box where somebody's making food and it would be the best meal you've ever had in your life."