Viewers take 'stay tuned' seriously

Alissa Krinsky, a single professional living in Chicago, has fallen in love with the hugely popular TV show "Desperate Housewives."

"It's not just a soap," says Ms. Krinsky. "It's funny, it's dark, and it's tantalizing. There's this great big mystery pulling you through the smaller story lines, too."

Krinsky is one of the millions who've turned high-concept shows such as "Housewives" and "Lost" into the most talked-about hits of the season. Almost no one, including most network executives, expected prime-time serials to make a comeback. The TV landscape has long been dominated by crime procedurals ("CSI," "Law & Order") and sitcoms ("Friends") which rely on self-contained story lines that audiences can easily follow. Fox's cult hit "24," returning in January, almost didn't go on air because of its intricate story arc.

Now that she's so smitten, Krinsky says that, as with any relationship, there is an implied "contract" between the show's writers and the viewers. "We agree to show up and in return, we expect the writers to keep delivering believable or captivating story lines," she says.

But as any fan - and scriptwriter - will tell you, long-term relationships don't always go as planned and sometimes the early promise of a great idea just doesn't play out. ("Twin Peaks," anyone?) The key is trust. Shows have to keep the romance alive by revealing some answers about the central mystery at the heart of the story each week - but without losing the intrigue of the show's premise. Most important, they have to convince audiences that they're not just stringing them along from week to week with nowhere special to go.

While a show's pilot may be meticulously planned, life after the honeymoon period tends to be a bit more chaotic.

"We still make it up as we go along," says Robert Cochran, the showrunner who oversees "24." "If we can shoot two episodes at a time, we're thrilled. Usually we're struggling and it's all we can do to keep track of one."

An enormous cast such as the 48 plane-crash survivors who populate the desert island of "Lost," would seem to dictate an equally enormous amount of forethought. But, says the show's creators, they were making the story up even as they were casting it.

"We wrote the [pilot] outline in five days," says executive producer J.J. Abrams. The studio greenlighted the show immediately, says Abrams, "and 11-1/2 weeks from that phone call, we turned in the final pilot."

But as with nearly all the good long-running serials, the show's creators have a handle on the big stuff - the mysteries and fundamental conundrums that lured viewers back after the first date.

"The way I have it planned, we're going to be building to some big reveals at the end of season one," says Marc Cherry, creator and executive producer for "Desperate Housewives." But he's already thinking ahead to fresh plotlines. "I've also laid in a couple of other mysteries that then will come up," he says.

While some fans may get nervous knowing that the road ahead is largely unmapped, others such as Elizabeth Arritt, a marketing director in Washington, says she likes the idea that she's engaged with something that is alive and responsive to the moment.

"Shows are more believable when they make it up as they go," she says. "They should keep a strong 'bible' of the show's history ... because fans notice when they mess it up," she says. "If they're so strictly set on a course, then they will miss opportunities that come along unexpectedly."

The biggest challenge is to ensure that the show's premise doesn't dry up too quickly.

"They either have to string people along past where it's believable or they have to end that arc and find new purpose," says Ms. Arritt.

Fans of J.J. Abrams's other hit show, "Alias," will remember that this is precisely what the creator did with central character, Sydney Bristow, in the middle of season two. He ditched the double-agent premise of the show and sent the whole story line in a new direction, with mixed results. While the show remains a darling of the critics, it has yet to break into the top ratings. Arritt, for one, applauds Abrams's bold move.

"Most creators say their show is like their child," she says. "If that's true, then they should treat is as such and let it grow up and have beginnings and endings that keep it living."

Krinsky is willing to forgive a show if it runs into a rough patch.

"I'd give a good show as much time as it needed to get back on track," she says. "Once I'm that loyal and excited I don't think that enthusiasm dries up so quickly."