October 9 will mark the mother of all NCIS: Los Angeles episodes.

As the team tracks down a suspect in a casino, four women - portrayed by the lead actors' real-life mothers - are playing poker. Check out the photo below, showing Daniela Ruah, Eric Christian Olsen, Chris O’Donnell and LL Cool J posing behind their respective moms, Katia Barker, Jeanne Olsen, Julie O’Donnell, and Ondrea Smith:

When creator Shane Brennan e-mailed the stars with the idea, "I thought it was a joke," Chris O’Donnell says. "When I found out he was serious, I was excited to call my mom. I knew this would be the biggest deal for her."

O’Donnell's mom, Julie, apparently enjoyed the experience. "She thinks this is her big break," the actor said with a laugh. "If 'Mom 2' appears in another script I'm sure she’ll answer the casting call."

It was a thrill for the NCIS: Los Angeles cast members themselves, as well. "It was fun getting to work and seeing her in hair and makeup," says Eric Christian Olsen of having his mother, Jeanne, on-set.

"It was like Yankee Stadium!" says LL Cool J of the deluxe motor coaches that brought the moms to the set, and were surrounded a makeshift Astroturf courtyard with potted plants and patio furniture.

Ondrea Smith, LL's mother, admitted, "I could get used to this!"

The scene took only a few hours to film, but the memories will last a lifetime.

"Acting with your mom? It's not something you get to do very often," Daniela Ruah says.

The moms' episode, "The Fifth Man," airs a week from tomorrow. This week's episode, "The Recruit," is all-new, and picks up after last week's NCIS: Los Angeles season premiere.

Steve Marsi is the Managing Editor of TV Fanatic. Follow him on Google+ or email him here.