Hollywood's major film and television studios and mediators were in last-minute talks on Wednesday, hoping to avoid a second industry strike.
SAG-AFTRA, Hollywood's largest union more commonly known as the Screen Actors Guild, has authorized a strike if negotiations do not result in a deal by midnight in Los Angeles (0700 Thursday GMT/UTC).
A-list stars, including Jennifer Lawrence and Meryl Streep, have voiced their support for the industrial action. Stars would not be able to promote new releases or attend industry events such as Comic-Con, which is set to be held next week, if the strike goes ahead.
The union represents roughly 160,000 actors and television and radio presenters and other media professionals.
What are the union's demands?
SAG-AFTRA is demanding higher compensation from streaming services as well as higher pay to counteract inflation.
In addition to salaries when working, actors earn "residuals" every time a production they star in is aired on network or cable.
However, streaming services such as Netflix and Disney+ do not disclose viewing figures and pay actors the same flat rate regardless of viewership.
The union is also demanding the implementation of safeguards around the use of artificial intelligence (AI). Actors want assurances that their digital images will not be used without their permission.
What has happened in negotiations thus far?
On Tuesday, union negotiators agreed to a studio request to bring in a federal mediator.
SAG-AFTRA said that studio representatives had "abused our trust" by leaking information to the media, and said that there would be no change in the Wednesday night deadline that would trigger a strike.
"We are not confident that the employers have any intention of bargaining toward an agreement," the union said in a statement late Tuesday. "Time is running out."
'Double strike' could bring almost all productions to a halt
The strike threatened by SAG-AFTRA follows similar action by the industry's main writers' union.
Early in May, the roughly 11,500 members of the Writers Guild of America (WGA) went on strike.
This disrupted most production for the autumn TV season and the filming of some big-budget movies.
The Alliance of Motion Picture and Television Producers (AMPTP) said it had offered "generous" pay raises but could not agree to all of the demands.
If SAG-AFTRA announces a walkout, this would lead to a "double strike" not seen in Hollywood since 1960 and halt most US film and television productions.