'Terminator' is back! AI experts do a reality check on Hollywood's new robo-nightmare

"Terminator: Dark Fate" also marks the return of writer/producer James Cameron -- who directed the first two movies in the franchise, but wasn't involved in the three sequels that followed. Although monstrous machines have figured in movie plots since Fritz Lang's "Metropolis" in 1927, Schwarzenegger's performance in "The Terminator" set the stage for worries about out-of-control intelligent machines. Billionaire techie Elon Musk is among the best-known doomsayers. "I keep sounding the alarm bell, but until people see robots going down the street, killing people, they don't know how to react because it seems so ethereal," Musk said in 2017. On the other side of the debate, Oren Etzioni, the CEO of Seattle's Allen Institute for Artificial Intelligence, or AI2, keeps telling people to calm down.