Kevin Bacon and Hilary Duff were among the big name stars joining fellow Hollywood actors and writers in a strike which has ground Tinseltown to a halt.
The pair are among some 11,000 actors who have joined members of the Screen Actors Guild to halt all productions by staging walkouts and forming picket lines outside major movie studios.
Actors are concerned about contracts keeping up with inflation, wages in the streaming era and more protections against the use of artificial intelligence mimicking their work on film and television shows.
Hollywood legend Bacon, 65, showed his support by joining activists on the streets of New York on Monday while brandishing a sign emblazoned “SAG-AFTRA ON STRIKE!”.
Disney Channel star Ms Duff, 35, was seen on the picket lines outside Paramount Studios in Los Angeles.
Other screen stars on the picket lines include Better Call Saul star Bob Odenkirk, actress Awkwafina and director Olivia Wilde.
Blockbuster films including the Gladiator and Avatar sequels are among those likely to be affected by Hollywood actors joining writers in strike action.
Sag-Aftra, which represents 160,000 actors, said members voted to strike for the first time in decades after talks with Hollywood film studios broke down.
No further talks are planned and there is no end in sight for work stoppages - the first time both writing and acting guilds have walked off sets since 1960.
Stars will no longer be allowed to promote their work through red carpet premieres and personal appearances, campaign for awards or participate in auditions or rehearsals.