There was a particular moment, children of the 1980s can tell you, when Teddy Ruxpin was everywhere. All the cool kindergarteners toted him to show-and-tell. He blinked his heavy eyelids at kids during the commercials between Saturday morning cartoons. Eventually, he even starred in his own animated series.

Teddy Ruxpin turns 30 this year, and today he represents a distinctive point in animatronics history. In some ways, he harkens back to an earlier era of automata—just the fact that his character rode on an airship makes him seem Victorian in a way—and yet the toy, at the peak of its popularity, was seen as futuristic. It was a time when home computers went mainstream and high tech meant objects that could talk—everything from teddy bears to Chryslers to Speak & Spell.

By today's standards, Teddy Ruxpin probably skirts the periphery of the uncanny valley— that's the concept used to describe the repulsion people feel when they see a robot that seems almost (but not quite) human. Really, he wasn't much more than a furry tape recorder. And Teddy Ruxpin certainly didn't look as much like a real bear as, say, this new version of Paddington Bear:

But there's something that many people still find grotesque or at the very least creepy about machines like Teddy Ruxpin. Just the tagline—"A Friend for Life Comes to Life"—seems a little ominous in an advertisement that depicts the bear as Frankenstein's monster.

Toys that talk and move have a long established place in the horror genre. (See also: Talky Tina and Chucky.) To be fair, there are plenty of stories of beloved toys, like Pinocchio and the Velveteen Rabbit, who come to life. But the possibility of an otherwise inanimate thing with human-like agency is potentially frightening, regardless of how real that inanimate thing appears to be.

For humans, feeling repelled by almost-but-not-quite-real-looking faces begins in infancy, scientists have found. And animals in the uncanny valley don't just seem eerie to us, but to other animals, too. In 2009, Princeton University scientists found monkeys reacted negatively to almost-real-looking monkey faces, suggesting a "biological basis" for the feeling we associate with the uncanny valley.

Real monkeys were disturbed and frightened by these computer-generated images of monkeys, scientists found. (Princeton University, 2009)

And yet the human inclination to produce lifelike representations of living things traces back for at least centuries. Ancient automata weren't just toys but works of art. Before the industrial age there were wind-powered statues. Later, there were mechanized pouncing tigers, clowns with clockwork guts, and automatons that smoke cigarettes.

"The writer," made by Swiss watchmaker Pierre Jaquet-Droz in the 1770s, is perhaps the most famous automaton. It has some 6,000 miniature parts, and is so intricate and sophisticated that it has been called the first computer.

Fast-forward 200 years to 1985, when Teddy Ruxpin was introduced with technology that had been around for decades. Talking dolls had only existed for as long as the history of recorded sound. From The New York Times' obituary of Teddy Ruxpin creator Ken Forsse, who died last year:

[Forsse's] technical breakthrough was coming up with electronic decoders to stuff in the faux animal’s plush head. They caused the bear’s face to yawn, frown and giggle in conjunction with the words emitted by a tape cassette implanted in its back. To create the effect, he used the same technology that produces music on a phonograph record in stereo, on separate tracks. In this case, one track carried sound and one track directed facial expressions and movements.

Those facial expressions, as people who have been in the same room as Teddy Ruxpin will tell you, are what made the toy unsettling. "Teddy Ruxpin is notorious for this," one commenter wrote on a TV Tropes forum about toys in the uncanny valley. "It's not the character design that pushed the toy into the valley... The feature that pushed the toy into the uncanny valley here is how his mouth moved combined with his static facial expression. In other words, an inactive Teddy Ruxpin is fine. A working one isn't. Especially when HIS BATTERIES ARE LOW."

And yet Teddy Ruxpin—like the Gremlinesque Furby that came after him—was riotously popular. Tens of thousands of Teddy Ruxpin dolls sold for $68 apiece in the first month they were available. (That’s equal to about $160 today.) By the end of that first year, more than 1 million had sold. Today, Teddy Ruxpin is mostly a memory immortalized on YouTube and among collectors online, who try to sell originals for as much as $200 apiece. Even as technology improves so that more and more lifelike robots and automata are made, Teddy Ruxpin's creepy place in pop culture is intact.

"Next time you're trying to fall asleep," one person wrote in the comment section beneath a vintage Teddy Ruxpin ad uploaded to YouTube, "try not to think about the hundreds of thousands of Teddy Ruxpin dolls in landfills. Waiting."