Unless you’ve been avoiding the Internet for the past decade, you’ve undoubtedly come across at least one of the massively popular videos that feature the explosive reactions that result when a piece of Mentos candy meets a bottle of Diet Coke or Coke Zero.

Today, nearly a decade after the first video featuring the candy-cola combo went viral, people all over the world continue to glue their eyes to watching Coke products froth away in the form of far-reaching geysers, bubbling baths, or even soda rocket-fueled cars. A quick search on YouTube reveals hundreds of thousands of such experiments – some of which are trending heavily on social media even today.

Lee Marek, a chemistry professor at the University of Illinois at Chicago, is credited for first popularizing the phenomenon when he thrilled a late-night TV audience in 1999.

But it was Fritz Grobe, a circus performer, and Stephen Voltz, a lawyer, who captured the world’s attention in 2006 when they turned 100 two-liter bottles of Diet Coke and 500 pieces of candy into a dazzling and foamy display. That three-minute clip, dubbed “Experiment #137,” has since been watched more than 100 million times across all platforms and was recently dubbed the fourth most iconic YouTube video of all time.

“We thought we had done something that was really cool,” says Voltz, “but there was no way to predict how widely it would spread around the globe.”

After the incredible success of that video, Grobe and Voltz, formed a production company called EepyBird Studios (rhymes with weepy), to handle media requests and calls from companies who wanted their help in creating their own viral videos. “It was amazing that in less than 48 hours it became a new full-time job for both of us,” says Grobe.

While the duo has since had success working with other consumer brands, Coca-Cola products have also starred in their subsequent viral hits, from their domino-inspired sequel, “Experiment #214,” which used 250 bottles of Diet Coke, to 2014's rhythmic video featuring Coke's environmentally friendly PlantBottle.

Eepybird rocket
Launching a Coke Zero-and-Mentos-powered mini rocket car.


Grobe and Voltz continue to perform their act live and in person at festivals around the world, where they’ve set world records for the number of Coke-fueled geysers involved, including one that featured some 2,850 participants in the Philippines. By their own estimates, the EepyBird team has used some 10,000 bottles of Coke products in their performances over the years – all of which have been subsequently recycled.

Behind the Magic

Based on their backgrounds, Grobe and Voltz might at first seem like an unlikely duo capable of setting the Internet on fire the way they have.

Grobe, the bearded and shorter of the pair, was touring as a professional juggler when he met Voltz, who was practicing law at the time, at a theatrical workshop in South Paris, Maine. After striking up a friendship, they realized they had similar tastes and styles when it came to performing. They then seized on the idea of turning the Diet Coke and Mentos combo into an act they would perform before an audience at the Oddfellow Theater in town.

While they spent hours preparing the choreography and components they would use in their show, Grobe and Voltz admit they neglected to think about costumes until the last minute. Then, as they rummaged backstage through the options that might fit them, they struck gold: two white butcher coats from the general store located next door. 

“We thought if we put on those coats we’d look like scientists,” says Grobe, adding that he and Voltz have kept the same look, complete with goggles, ever since.

Eepybird headshot
Stephen Voltz (left) and Fritz Grobe, the duo behind Eepybird.

When they look back at their journey together, Grobe and Voltz point to a single element that helps explain their success: their videos build an emotional connection with viewers.

“We have gotten emails from people all over the world, from Ukraine to Brazil, letting us know that watching our videos has brought a smile to their day even in the toughest of times,” says Grobe, who co-authored a book with Voltz called The Viral Video Manifesto. “We simply wanted to create something fun that would appeal to people. But it has had such a huge impact on us knowing we have given people the ability to smile.”

Grobe and Voltz also say they are thrilled that they have helped inspire so many others to make Coke-powered geysers of their own.

“We love seeing people do crazy things,” says Voltz. “It’s part of our DNA to want people to do this kind of thing for themselves. That’s what makes it so much fun.”