Science-fiction films have often been the domain of grand designs and sweeping cityscapes, but over the past decade we’ve seen a more grounded approach to the genre. Movies like Her, District 9, and Looper put the focus on gritty, lived-in worlds filled with technologies that are clear descendants of the tools we use today. Here at Sundance, a new sci-fi drama from writer-director Jake Paltrow is joining that movement.

Young Ones tells the story of a family struggling to survive in a future where water shortages have turned entire sections of the country into barren desert. It’s a world where every day is a struggle and flashy new technology is the exception, not the rule. But when it came time to imagine what the machines of tomorrow might look like, Paltrow enlisted the masters of modern robotics: Boston Dynamics, the robotics company recently purchased by Google.

Shannon provides for his family by trading supplies, so when his flesh-and-blood mule breaks a leg he’s forced to spend what little money he has on a "simulant" — a robotic mule recreation. It’s essentially a packing crate with spindly legs that can handle all manner of terrain, and to those following robots the quadruped will look awfully familiar.

"I’ve always been interested in robotics," Paltrow says, "and while I was writing it I went up to Boston Dynamics and got to spend a little time with Marc Raibert and his team." This was back in 2008, when the script was in its early stages and BigDog was the company’s flagship robotic beast. Paltrow realized it would be a perfect fit for the world he had in mind for Young Ones.

Initially, he hoped to use an actual BigDog unit as an actor in the movie. "We spent a lot of time trying to work out a way to do it," he says, but BigDog’s combustion engine would have made recording sound on set impossible. Post-production dubbing could have solved that problem, but additional complications made it clear that BigDog just wasn’t ready for the big screen. "It was ultimately something that was sort of small potatoes for them to do a movie," he concedes.

Instead, the production moved forward with a mix of replicas and visual effects. During production a partial reproduction of the robot was filmed alongside the actors. "The machine is really a plastic and fiberglass torso," Paltrow explains, "and we had these two performers in grey leotards, these two great parkour guys, who could run up the rocks and do a whole thing." The movement of the legs in the finished film — and it’s as convincing an illusion as one could hope for — came courtesy of the film's visual effects wizards.

While watching the film, it’s clear that hewing so close to reality grounds Young Ones in a way that pure speculative design on its own wouldn’t. Even the single glimpse we get of a futuristic phone — a sleek handset that slides open like a fan to reveal a selection of touchscreens — seems to be a believable, logical evolution. Paltrow says that feeling of realism was something he strived for throughout all elements of the world, and is particularly important to contemporary audiences.

"I think there’s a general feeling [that] authenticity seems to be the number-one quality for anything these days," he says. "Maybe that’s because it’s so easy to explore so many things now. I just think people’s bullshit detectors are much more fine-tuned now than they were when i was a kid." In the past, hearing a song on the radio might kick off a multiday hunt to find out the song’s name, he cites as one example; now the information is available with the simple launch of an app or a website search. "So it’s just a very different world, and in some ways I guess that means it’s less naive." He pauses, considering his next thought carefully. "That’s probably a good thing."