Actors have joined screenwriters on the picket line in a rare dual strike, effectively bringing Hollywood to a standstill for the first time in decades.

The Writers Guild of America went on strike against major studios in May to push for contract provisions including higher wages, more residuals, guaranteed staffing minimums and regulations on artificial intelligence.

SAG-AFTRA, which represents Hollywood actors and performers, followed suit last week after the two sides failed to reach an agreement over sticking points including residuals from streaming platforms and the use of AI (especially when it comes to actors' digital likenesses).

SAG-AFTRA's rules prevent striking performers from acting, singing, dancing, doing stunts and promoting their projects, whether on red carpets or award shows. Meanwhile, WGA members are prohibited from providing any writing services to a struck company.

Erin Hill, an associate professor of media and popular culture at UC San Diego (who has worked in the industry but never been part of a Hollywood union), says she's both "terrified by and optimistic about'' the strike, which comes at a critical moment technologically and economically.

"I just think it's a really, really, really important stand that needs to be made now, preferably yesterday, and also at every subsequent strike for the next however many cycles until this gets sorted, because this is going to become an extremely untenable — even more so than now — kind of labor squeeze otherwise," she tells NPR over Zoom.

As Hill puts it, there has been a strike roughly every decade for almost a century as new mediums succeed each other, from television to cable to VHS to mobile to, now, streaming. SAG performers last went on strike in 1980, while screenwriters did most recently from late 2007 to early 2008.

This is the first dual strike since 1960, when the WGA and what was then just SAG (more on that later) collectively shut Hollywood down for about six weeks. Those strikes resulted in union members getting health care and pensions, and a residual system to compensate them when their movies aired on TV.

How — and when — might things resolve this time around?

The strike could last into the fall or even longer, which would significantly disrupt everything from fall film festivals to the fall TV lineup (and possibly next summer's blockbusters) to the Emmy Awards (which are scheduled for mid-September and likely to be postponed, with an announcement expected by the end of this month).

Ronny Regev, a historian at the Hebrew University of Jerusalem and the author of Working in Hollywood: How the Studio System Turned Creativity Into Modern Labor, tells NPR over email that it won't be surprising if the actors settle before writers do.

"At the end of the day, this is all related to the position of these workers in the production process," she adds. "Since producers can survive without new written material for a while, WGA has less bargaining power than actors and directors."

Hill says the best-case scenario is that the two unions stick together for long enough to put so much pressure on studios and networks that they start to make deals.

"Whoever gets left sitting alone on one side or another of the table is going to have less power in the end," she adds.

Here's a look at how earlier strikes set the stage for this latest fight — and what they can tell us about what happens next.

The industry is constantly reacting to technological changes

Every new kind of technology creates not only different arrangements of labor and management, Hill says, but new forms of content that become popular and earn revenue.

She points to the rise of television in the '40s, cable (and reuse fees) in the '60s and '70s, VCR and VHS in the '80s and mobile and internet in the early aughts.

"Many, many, if not every strike, is in some way kind of trying to catch up to a technology that has already kind of emerged and/or the content and the kind of growing popularity of certain content that has come out of that technology," she says, with streaming and AI being the latest.

She says the 2007 WGA strike has a lot in common with the current one because of the "labor arrangements being negotiated for production in a new medium," since at issue aren't just streaming TV and film production residuals but also working conditions and fundamental intellectual property concerns.

Regev also sees similarities with the last dual strike of 1960, which she says was also about "the place of actors and writers in this changing world." In that case, the unions were primarily concerned about the effect of television on the film industry (they also pushed for employer-based health insurance, she notes).

The fact that the unions are talking about AI now suggests to Regev that they're not just concerned about the present moment, but trying to establish assurances about the near future as well.

Future contracts — or future strikes in protest of them — will continue to reflect technological change, both experts say.

"If they reach some concessions on A.I. maybe that would entail a long period of harmonious relations," Regev writes. "If they kick this can down the road (as they did with television throughout the 1950s) then that could mean another strike/dispute in the coming years."

There's strength in numbers — but the unions aren't equal

The fact that both unions are striking at the same time puts extra pressure on studios and streamers.

There are a lot of people involved: WGA says it has some 11,500 members, while nearly 65,000 SAG-AFTRA members are on strike (there are others, including many NPR journalists, who are under a different contract and therefore not on strike).

Another big difference between today's strike and those of recent decades is the makeup of the unions themselves: It was only in 2012 that the Screen Actors Guild (SAG) merged with the American Federation of Television and Radio Artists (AFTRA) to form SAG-AFTRA.

Ben Mankiewicz, Turner Classic Movies host and Hollywood history buff, told Morning Edition this week that the merger was "from a labor point of view, wise," adding that there's strength in numbers.

"I think undoubtedly that will lead to a better deal for the actors," he said. "I don't know if it'll lead to a good deal for the actors, but it'll lead to a better deal."

Hill says the primary reason Hollywood even has a stand to take at this moment is because of its relatively large unionized portion of key workers. In other industries, she says, people who are as powerful as a major TV writer like Shonda Rhimes would be management and not eligible for unions.

"So because of this labor, it's possible for this kind of industry to actually put its foot down to a degree," Hill adds. "How big a degree will depend on the strike."

WGA and SAG-AFTRA are not your typical unions, Regev agrees: They are unequal. She writes that they have some highly paid members, namely the big stars, and then the rank-and-file members who are "far from rich."

"While someone like George Clooney or Fran Drescher can certainly afford not working for a while, the vast majority of actors cannot afford that," she adds. "That's what producers are counting on."

Plus, Mankiewicz notes, writers have already been on strike for 2 1/2 months. He predicts that by the early fall there will be "some fissure among producers" — and "a desire of some significant people with weight to get back to work."

Public support, which has fluctuated over time, is key

The success and failure of strikes over the years also has to do with other national, world and economic events, Hill says.

She says the current cultural and societal moment gives her hope that the unions will prevail, adding that her college students "seem to get what labor movements and strikes are about in a way that ... students I had worked with even 10 years ago did not not have this kind of blind acceptance."

Hill says it's typically very easy for ordinary people to dismiss movie stars' complaints — but the public seems to be moved by renowned actors walking out of movie premieres and marching on picket lines.

She points to an incident in late May, where students protested outside of Boston University's commencement as Warner Bros. Discovery President and CEO David Zaslav gave a speech.

Writers and actors are uniquely suited to make their case, she says, because of their rhetorical prowess and name recognition.

"People identify their favorite things with those people," Hill adds. "So there's a humanization that happens. ... I think psychologically in the country and in Hollywood, there's more of ... this kind of willingness to sit down and actually make a stink."

Hill also acknowledges that that's easier said than done: Just how much unemployed actors and writers will be able to push through psychologically, emotionally and financially remains to be seen.

But she says these unions are, at least in some ways, able to take up a fight that many members of the public cannot.

"They stand for something that people, I think, are also feeling in their jobs, where they don't have power to negotiate against somebody who's saying, 'You know what I would like you to work from home and just be moving your mouse 12 hours a day and I also want you to do X, Y and Z and I'm going to time you,' or whatever it is," Hill says. "They don't have that power. I think Hollywood needs to do it now, and I'm proud that they're doing it."