Hollywood's striking actors fear that artificial intelligence is coming for their jobs -- but for many stunt performers, that dystopian danger is already a reality.
From "Game of Thrones" to the latest Marvel superhero movies, cost-slashing studios have long used computer-generated background figures to reduce the number of actors needed for battle scenes.
Now, the rise of AI means cheaper and more powerful techniques are being explored to create highly elaborate action sequences such as car chases and shootouts -- without those pesky (and expensive) humans.
Stunt work, a time-honored Hollywood tradition that has spanned from silent epics through to Tom Cruise's latest "Mission Impossible," is at risk of rapidly shrinking.
"The technology is exponentially getting faster and better," said Freddy Bouciegues, stunt coordinator for movies like "Free Guy" and "Terminator: Dark Fate."
"It's really a scary time right now."
Studios are already requiring stunt and background performers to take part in high-tech 3D "body scans" on set, often without explaining how or when the images will be used.
Advancements in AI mean these likenesses could be used to create detailed, eerily realistic "digital replicas," which can perform any action or speak any dialogue its creators wish.
Bouciegues fears producers could use these virtual avatars to replace "nondescript" stunt performers -- such as those playing pedestrians leaping out of the way of a car chase.
"There could be a world where they said, 'No, we don't want to bring these 10 guys in... we'll just add them in later via effects and AI. Now those guys are out of the job."
But according to director Neill Blomkamp, whose new film "Gran Turismo" hits theaters August 25, even that scenario only scratches the surface.
The role AI will soon play in generating images from scratch is "hard to compute," he told AFP.
"Gran Turismo" primarily uses stunt performers driving real cars on actual racetracks, with some computer-generated effects added on top for one particularly complex and dangerous scene.
But Blomkamp predicts that, in as soon as six or 12 months, AI will reach a point where it can generate photo-realistic footage like high-speed crashes based on a director's instructions alone.
At that point, "you take all of your CG (computer graphics) and VFX (visual effects) computers and throw them out the window, and you get rid of stunts, and you get rid of cameras, and you don't go to the racetrack," he told AFP.
"It's that different."
- The human element -
The lack of guarantees over the future use of AI is one of the major factors at stake in the ongoing strike by the Screen Actors Guild (SAG-AFTRA) and Hollywood's writers, who have been on the picket lines 100 days.
SAG-AFTRA last month warned that studios intend to create realistic digital replicas of performers, to use "for the rest of eternity, in any project they want" -- all for the payment of one day's work.
The studios dispute this, and say they have offered rules including informed consent and compensation.
But as well as the potential implications for thousands of lost jobs, Bouciegues warns that no matter how good the technology has become, "the audience can still tell" when the wool is being pulled over their eyes by computer-generated VFX.
Even if AI can perfectly replicate a battle, explosion or crash, it cannot supplant the human element that is vital to any successful action film, he said, pointing to Cruise's recent "Top Gun" and "Mission Impossible" sequels.
"He uses real stunt people, and he does real stunts, and you can see it on the screen. For me, I feel like it subconsciously affects the viewer," said Bouciegues.
Current AI technology still gives "slightly unpredictable results," agreed Blomkamp, who began his career in VFX, and directed Oscar-nominated "District 9."
"But it's coming... It's going to fundamentally change society, let alone Hollywood. The world is going to be different."
For stunt workers like Bouciegues, the best outcome now is to blend the use of human performers with VFX and AI to pull off sequences that would be too dangerous with old-fashioned techniques alone.
"I don't think this job will ever just cease to be," said Bouciegues, of stunt work. "It just definitely is going to get smaller and more precise."
But even that is a sobering reality for stunt performers who are currently standing on picket lines outside Hollywood studios.
"Every stunt guy is the alpha male type, and everybody wants to say, 'Oh, we're good,'" said Bouciegues.
"But I personally have spoken to a lot of people that are freaked out and nervous."