Hollywood actors will join writers on the picket lines for the first time since 1960.

SAG-AFTRA — the union that represents approximately 160,000 actors, announcers, recording artists, and other media professionals around the world — announced a strike will begin on Thursday at midnight after failing to negotiate a deal with the Alliance of Motion Picture and Television Producers (AMPTP), which bargains on behalf of studios including Disney (DIS), Netflix (NLFX), Amazon (AMZN), Apple (AAPL), and NBCUniversal (CMCSA).

"Unfortunately, they have left us with no alternative," said Duncan Crabtree-Ireland, SAG-AFTRA national executive director and chief negotiator, at a press conference Thursday afternoon. He called a strike “an instrument of last resort."

It is the first time SAG-AFTRA has gone on strike in over four decades. The WGA strike is currently in its third month with no end in sight.

The union extended the negotiation deadline last week and even met with federal mediators earlier this week — a last-ditch effort to try and reach an agreement, which ultimately failed.

SAG-AFTRA is fighting for more protections surrounding the role of artificial intelligence in media and entertainment, in addition to higher streaming residuals as more movies and TV shows go direct to streaming. These demands are similar to those posed by the writers' guild.

Disney CEO Bob Iger slammed the looming strike during an interview with CNBC earlier on Thursday.

"It’s very disturbing to me," he said, describing the respective union demands as "not realistic" given the current media environment. "We’ve talked about disruptive forces on this business and all the challenges we’re facing, the recovery from COVID which is ongoing, it’s not completely back. This is the worst time in the world to add to that disruption."

'A potential scenario of massive churn'

Indeed, KPMG’s US national media leader Scott Purdy previously told Yahoo Finance that with actors joining the picket lines, audiences should prepare for re-runs and extended delays for TV shows. That's not all.  

"TV and streaming services, especially those without significant international content to lean on, will run out of content soon," Purdy added. "While this might save studios and networks some short-term production budget, what people aren’t talking about is how this creates a potential scenario of massive churn for streaming services and for weaker audience metrics for TV networks, which could hurt advertising revenue."