The word robot was coined in 1920 by the Czech writer Karel Capek in his play R.U.R.–the acronym stands for “Rossum’s Universal Robots.” If like most people you’ve never actually seen R.U.R., you may not know that it ends with the extinction of humanity at the hands of the robots–all except for one man, a clerk named Alquist, and you don’t get the impression he’s long for this world. It’s all a big metaphor for the industrial proletariat seizing the means of production from capitalist overlords.
Amazingly, almost 100 years later, movies are still telling stories about killer robots wiping out humanity. It’s turned out to be one of our most enduring nightmares. The villain in Avengers: Age of Ultron is a robot who wants to wipe out humanity. The villains in Terminator Genisys (in theaters July 21) are robots who want to wipe out humanity. The henchmen of the villain in Tomorrowland (May 22) are robots who want humanity to wipe itself out. To say whether the robot in Ex Machina wants to wipe out humanity would be saying too much, but you are definitely going to want to keep an eye on her.
If there’s a difference between these movies and R.U.R., it’s that the robots aren’t metaphors anymore. These films aren’t about capital and labor, or the philosophical nature of personhood, the way Blade Runner was. They’re about robots literally threatening to wipe out humanity. Somewhere between 1920 and now the existential threat of robots passed out of the hypothetical and symbolic and into the realm of the literal and actual.
Terminator is the current reigning warhorse of this particular genre: it’s been around since 1984 and hasn’t even been rebooted yet (though we have seen five different actors play John Connor). In this summer’s installment, Kyle Reese, Connor’s durable offsider (and, actually, I think, his father), winds up in an alternate timeline in which Sarah Connor was raised and trained by a Terminator after another Terminator, an evil one, killed her parents. In a surprise but also strangely inevitable twist, we get to see a fight between present-day, 67-year-old Arnold Schwarzenegger and vintage 1984-era Arnold Schwarzenegger.
But if the Terminator movies are a cautionary tale, they haven’t done much to deter humanity’s robot-building compulsion. DARPA–the high-tech mad-science arm of the Defense Department–is currently winding up a three-year, 25-team competition to build humanoid robots; the leading team after the semifinals has been acquired by Google. So far the robots can perform only simple tasks, like walking across rubble and making a hole in a wall, and most of the time it’s all they can do to keep from falling over. But they do look remarkably like the Terminator, at least in its skeletal, defleshed form.
The DARPA robots are supposed to be for protecting humans, not for terminating them–they’re designed for rescue missions under hazardous circumstances, like the Fukushima disaster. But if there’s one thing Avengers and Terminator agree on, it’s that that’s how it starts. Skynet, the rogue artificial intelligence that created the Terminators, was supposed to run America’s defense systems for us. (There is in fact a real Skynet: that’s what the NSA, tempting fate, named the software it uses to scan communications data for evidence of terrorism.) Ultron started out as Tony Stark’s attempt to build “a suit of armor around the world,” which would create permanent peace. Needless to say, it doesn’t do that.
A lot of very smart people think very seriously that robots, or at least artificial intelligences, may rise up against us in real life. Stephen Hawking bluntly told the BBC in December, “The development of artificial intelligence could spell the end of the human race.” Elon Musk, the entrepreneur behind PayPal, SpaceX and electric-car maker Tesla, invests in AI research just to keep an eye on a technology that is, in his words, “potentially more dangerous than nukes.” (When there’s a technology that Musk doesn’t want to build, you know something’s off.) “With artificial intelligence we are summoning the demon,” Musk has said. “In all those stories where there’s the guy with the pentagram and the holy water, it’s like–yeah, he’s sure he can control the demon. Doesn’t work out.” Musk thinks the potential for dangerous AI is at most 10 years away. Maybe five.
All this robophobia is part of a broader, deeper vein of fear that runs through this summer’s movies: the fear of unintended consequences. Humanity seems to be losing faith in its ability to predict the results of its own actions. Hence Jurassic World (June 12), in which scientists create a new hybrid dinosaur using DNA from four other, already extremely scary dinosaurs, because it might be fun. In Tomorrowland, four geniuses–Jules Verne, Nikola Tesla, Gustave Eiffel and Thomas Edison–design a utopia with unexpected consequences, and George Clooney’s character invents a truly disruptive machine that predicts the future. Hitman: Agent 47 is about a genetically engineered assassin who goes rogue–he’s even deadlier than the previous 46 genetically engineered assassins! And so on. What makes these fantasies so compelling is that they’re not fantasies anymore: in April, Chinese researchers announced that for the first time they have edited the DNA of a human embryo.
The other major difference between these movies and R.U.R. is that in summer movies the human beings usually win in the end. In R.U.R., they don’t. Maybe as robots have gotten more real, the stories we tell about them have actually gotten less realistic, not more so.
Then again, Capek’s other major work was a novel in which humanity loses a war with a race of intelligent newts. So it’s possible he wasn’t right about absolutely everything.
This appears in the June 01, 2015 issue of TIME.