Last year, only a few fictional residents of Newport Beach were aware of the joys of Chrismukkah, the blended holiday that is now sweeping at least some portion of the nation thanks to FOX's "The O.C." The festival that millions of over-Christmased young Jewish children never knew they needed celebrates its second anniversary on Thursday (Dec. 16) night's episode of the FOX soap.

"I grew up, as a lot of young Jewish boys do, envious of all the Christmas holidays that went on," says "O.C." creator Josh Schwartz. "When it came time to figure out what the holiday was for the Cohens, interfaith, I wanted to try to come with a holiday in the vein of Festivus from 'Seinfeld.' We started bandying around interfaith holiday names -- you know, Hannumas -- and someone in the writer's room said 'Chrismukkah' and that was it."

The identity of the influential scribe has vanished into the wind, but in "The Chrismukkah That Almost Wasn't," the name of the blended holiday becomes a mantra, repeated by nearly every major character with an insistence and cadence that suggests a mellow Mamet on a Manischewitz bender ("Merry Chrismukkah" "Chrismukkah?" "Yes, Chrismukkah" "What do you mean by Chrismukkah?"). Filled with the Chrismukkah spirit, Adam Brody's Seth Cohen launches a campaign to bring his annual jubilee to the masses, creating new holiday icons and attempting to pen a holiday anthem. Seth's determination to give his creation the trappings of a mainstream jubilee mirrors Schwartz's minor disappointment with his own Hanukkah memories.

"What Jewish boy or girl growing up doesn't feel a little jealous?" he ponders. "They get all the good songs. They get the tree. They have all the characters -- Frosty and Rudolph. We've got dreidels. It's not really the same."

However, Schwartz and Seth are also well aware that Chrismukkah is, by its very fabricated nature, right on the edge of over-exposure. After the first season of "The O.C." featured special episodes celebrating Chrismukkah, New Years, Thanksgiving and Passover, the show's scribes have a pretty good idea of how to write holiday episodes that seem organic to the show's master narratives.

"Last year we felt like it got some nice traction, but we felt like we could come back to it this year," Schwartz says.

In addition to regular reminders of last season's episode -- Summer (Rachel Bilson) in a Wonder Woman costume and Marissa (Mischa Barton) busted for shoplifting -- and plenty of the self-referential humor that the show's fans adore, "The Chrismukkah That Almost Wasn't" is a surprisingly emotional affair with earnest and heart-felt work from some of the cast's older actors including Alan Dale and Kelly Rowan.

"There's all the sort of Chrismukkah kind of self-awareness in the episode, but there's so much stuff happening in terms of impacting these characters that it pulls them back down," explains Schwartz.

Facing the three-hour finale of "The Apprentice" on NBC, it may take a Chrismukkah miracle for "The O.C." to get any ratings boost from the holiday.

"We do it was gonna be tough on Thursday," Schwartz says. "We have our core viewers and we're hoping word-of-mouth will build as the show really starts to pick up. Last week, this week all the set-up is starting to pay off and things are about to start getting crazy."