Will Hollywood writers strike? Labor drama unfolds.

Hollywood writers generally know where a story is headed when they sit down to write scripts for TV shows and movies. But the final act is up in the air as the entertainment industry braces for a possible strike by the Writers Guild of America (WGA), which would be the first in nearly two decades.

If writers were to strike after the Oct. 31 deadline for a new contract, viewers could see the impact on their TV screens by Christmas or even a little sooner – in the form of a greater offering of unscripted reality shows, reruns, and specials. After that, selection at the local cineplex would be affected, as studios dole out lower-quality movies they already own but that have been sitting on the shelf.

Negotiations between TV writers and the Alliance of Motion Picture and Television Producers (AMPTP) have languished since July, and the WGA is expected on Friday to announce that its members have voted to authorize a strike, if it comes to that.

For both sides, the deal-breaker question is how to allocate profits from new media – work disseminated on everything from the Internet to cellphones to iPods.

"The source of our difficulties lies with the rapid technological and commercial changes that have been occurring within this industry," said Carol Lombardini, AMPTP executive vice president of business and legal affairs, in a statement.

AMPTP has called for a revamp of the decades-old system of so-called residuals, the fees paid to writers, actors, and other talent when a show is reused.

Producers have argued that they should pay out residuals only after they have recouped their investments in a TV show or a movie, which has become harder to do now that the audience is more fragmented thanks to competition from cable, satellite TV, webcasting, and other viewing options. They dropped that "recoupment" provision in a surprise move Tuesday, but they continue to emphasize their unwillingness to expand residual payments to cover the digital world of DVDs as well as TV shows and movies online, as the WGA has demanded.

Meanwhile, the WGA is drawing its line in the sand. "What this [strike authorization vote] means is that the guild is in fact serious about our proposals, is willing to go to the table to negotiate a deal, and is not going to back down," says Gregg Mitchell, spokesman for WGA West. A vote to authorize a strike does not necessarily mean the WGA will strike, but it signals that the members will back the union leadership if it deems a strike is necessary, says Mr. Mitchell.

Just the possibility of a writers' strike is reverberating through the industry. Like farmers before a tornado, production houses are taking steps to weather any writer shortage. Some longstanding TV shows, such as "Law & Order," continued to shoot after others had gone on summer hiatus, with the aim of stockpiling episodes.

But a frantic air hangs over many freshman dramas, particularly ones such as CBS's "Moonlight," a vampire serial that arrived late to the schedule. A work stoppage could be a stake to the heart to that show and others like it, observers say.

"It will just kill a new show like us," says Chris Fisher, who directed the seventh episode, which airs in a few weeks.

Most scripted shows work only four to six weeks in advance. That means the current crop will run out of original episodes just in time for the holidays. Hollywood has weathered such strikes before, but they've had lasting impact on creators and yielded gaps in quality for viewers.

The stakes are higher this time, say many observers, because the industry seems more fragile and fragmented. Because viewers have so many new options, it's not as easy as it used to be to hold onto them.

"Who even knows what TV or all this will ... look like pretty soon?" asks Mike Langworthy, a veteran scriptwriter for shows as diverse as "8 Simple Rules," "The Drew Carey Show," and "Cybill." If loyal viewers are left hanging, he worries, they won't come back.

"Everybody is watching YouTube and two-minute movies online. That's why this is all so important, economically," says Mr. Langworthy, adding that he's moving on as well – an option that he says will beckon many writers, young and old, if the strike happens.

The prospect of a labor action was the tipping point in a career move he'd planned to make later in life: to become a high school teacher. "The thought of having to rebuild a career after a long, divisive strike made it easy," says the comedy writer. "My son had been pushing to go to school back east, so we just put it all together and the strike was the last straw."