The Intimidating Task Behind This Season's Cutest Breakout Star

Enlarge this image toggle caption Jordan Strauss/Invision/AP Jordan Strauss/Invision/AP

Sometimes an aging movie star must sit and watch as a charismatic newcomer steals the spotlight — even inanimate ones. R2-D2, the adorable little robot — or droid — first appeared in Star Wars in 1977. And over the years he's faced cute competition from Yoda, and the Ewoks. But the latest Star Wars movie, The Force Awakens, brings us what might be an even cuter new droid: BB-8.

These days, the two men who built BB-8 have gotten used to people cooing over the droid's soulful, giant eye and its sweet, round silhouette. Matthew Denton supervised electronic design and development for the movie's characters; Joshua Lee is a senior animatronic designer.

Some fans mocked BB-8 when its images first went public, for looking like a soccer ball, among other harmless things.

"It's got similar proportions to a baby," says Lee.

"And it has characterizations of a puppy," says Denton. "Like a puppy dog."

BB-8 was first imagined by the film's director, J.J. Abrams, who sketched the little droid on a napkin in 30 seconds, Lee says.

When they got that sketch, Lee and Denton were asked to devise a robot not dependent on digital effects. Abrams wanted to avoid CGI whenever possible.

"We weren't really sure whether it was possible to achieve BB-8 physically," says Lee. "In fact, it was only about a week to go before filming began that we actually had the physical droids there for J.J. to look at."

BB-8 is a robot on a mission, discovered by a girl on a desolate planet. It took about a year of testing and building to come up with all the BB-8s used in the movie, Lee says.

"We built seven different versions of BB-8 to get all the shots we needed to," says Lee. "And they all got nicknames," adds Denton.

'The Wiggler" was for close-ups, given that it wiggles around in one place, "turning its head and tilting its body," says Lee.

The "Bowling Ball" was literally bowled through shots whenever the droid had to move fast.

And when BB-8 had to emote, there was a special puppet version, nicknamed, quite simply, "The Puppet."

"A puppeteer was physically controlling the puppet through rods and levers," says Lee. "That was incredibly expressive."

And expensive — those rods and levers had to be digitally removed.

Now imagine you're Denton, who built BB-8, and your job was to remote-control it. It wasn't always so much fun, he says, on set in Abu Dhabi, where temperatures regularly exceeded 120 degrees.

"You couldn't touch your hand on anything if it was metal — you didn't pick it up because you'd burn and it was like working on another planet," he says. "But I guess it was the point."

Here's the wildest part. Denton and Lee had a list of things they knew the droid needed to do, including speed over sand, navigate through forests and climb down stairs. But they never saw a word of the script until the movie started shooting.

"We didn't know how much BB-8 was in the movie and I've only realized what a huge deal it is actually," says Denton.