The post-mortem on ''The O.C.''

It spawned one of the stickiest TV catchphrases of the last few years, introduced ”Chrismukkah” to the national lexicon, and made comic-book geeks suddenly sexy. It revived the dormant teen-soap genre, brought emo to the masses, and helped make irony so cool that it wasn’t. And now, in fewer than four years, Fox’s once-signature drama The O.C. has gone from pop-culture-permeating phenomenon to cancellation.

When Fox announced on Jan. 3 that The O.C.‘s Feb. 22 episode would be its series finale, there was one question to be asked: How did a show whose first season was so hot flame out so fast? The answer lies in the nature of the modern TV landscape, where new series come and go in one episode and big buzz is often followed by big backlash. The O.C. debuted to impressive numbers in August 2003, drawing 7.5 million viewers and turning its mostly unknown cast into bona fide stars. Soon came a supersize 27-episode season order, along with an insatiable fan appetite for the show’s fast-paced action. ”We burned through a lot of story [in season 1],” says creator-exec producer Josh Schwartz. ”We wanted to put it all out there on screen, and that’s why the first season was so fun.” Adds Craig Erwich, Fox’s exec VP of programming, ”The show just hit a nerve — [they had] to go for it.”

But then came the hangover: Massive media attention meant that by season 2, some fans decided that The O.C. was no longer too cool for school. ”It’s like being a band,” Schwartz says. ”The cool kids discover you, then you become super popular, and that audience goes, Oh, I can’t like it.” It didn’t help that with only four core teen characters — who’d already fought and made up ad nauseam — Newport Beach started to feel awfully claustrophobic. ”I don’t know that shows like this are necessarily designed to run forever,” Schwartz explains, ”but just to be a blast while they’re on.”

The O.C.‘s unique blend of comedy and over-the-top melodrama was a blast — at least most of the time. ”When it worked,” says Schwartz, ”it was something you hadn’t seen before.” When it didn’t, an audience-infuriating nut named Oliver materialized, as did gratuitous girl-on-girl action. And in a semi-shocking development last May, the lead female character died in a car crash. ”We were trying to keep pace so as to not get canceled, and it got overcooked,” admits Schwartz. Yet he defends those widely derided story lines. ”People still talk about them, for good or ill. When we didn’t do anything, people would be like, ‘Why hasn’t anyone gotten drunk or gotten in a fight?”’ Adds Benjamin McKenzie, who broke out as punch-happy bad boy Ryan Atwood, ”At some point you’re going to have feelings about doing the same thing over and over again. Around the third season, we reached a slow point. That was hard.” Even harder were three time-slot changes — the most fatal being a switch from American Idol-driven Wednesday to ultra-competitive Thursday. Once Grey’s Anatomy moved onto its block last fall, says Schwartz, ”we kind of knew what was going to happen.”

One bittersweet coda: The O.C. is now enjoying a creative — though not a ratings — resurgence. (It’s currently averaging only 4.1 million viewers weekly.) ”I wanted to remind people of the first season,” says Schwartz of lighter plots like Seth and Summer’s on-and-off engagement and the surprisingly sweet romance between Ryan and Taylor Townsend. ”It was really creatively liberating, not worrying about ratings.” Cast members agree — especially 28-year-old McKenzie, who’s spent four years playing a teen. ”It feels like a natural death,” says the actor. ”We’re surrounded by family and friends, and we’ve said all the nice things we want to say to each other.” But could The O.C. be resuscitated on The CW, as rumored? Not likely. ”You don’t want to stay too long at the party,” quips Schwartz, who’s now developing the teen soap Gossip Girl at The CW, and the spy comedy Chuck for NBC. ”Because somebody might start a fistfight.”