Netflix’s popular series, Stranger Things, a drama about a 12-year-old boy gone missing in rural Indiana in the 1980s, first aired in 2016. The story follows the search efforts of his mom (played by Winona Ryder), local authorities, his friends, and a girl with telekinetic powers, and reveals information about secret paranormal experiments the government was conducting near their town.

On the day season two of the series was released, a social media storm began to brew. In the first episode, beloved character Dustin Henderson donned a purple hoodie imprinted with a retro Science Museum of Minnesota logo and Brontosaurus “thunder lizard” design; it quickly went viral, attracting attention worldwide. That unintentional product placement helped raise more than a half-million dollars for the museum’s programming and provided access to STEM education programs for hundreds of thousands of children across the state. Kim Ramsden, then communications director for SMM, attributed the success largely to the museum’s nimble marketing and communications team, who were ready and willing to roll with it.

“At the time, we didn’t know much about the history of the shirt,” said Kim. “We started digging in right away, to find out if it was real and where the design came from.”

Within days they were ready to offer eager fans hoodies and t-shirts with the same thunder lizard design that had been offered in conjunction with a 1980s museum exhibition.

When developing social media strategies, the business owners and authors I work with have often asked, “How do we go viral?” Though the Science Museum’s product placement was unintentional, there is much to be learned from what happened in the minutes, hours and days that followed the thunder lizard hoodie reveal. Here are four of the most important lessons in virality gleaned from the museum’s experience:

Know Your Audience

This story revealed just how much people love the Science Museum, science, and specifically, dinosaurs. Since the Brontosaurus was discovered, its classification and name have been hotly debated. More than a century ago, the wrong head on a Brontosaurus body led to its reclassification as an Apatosaurus. To the delight of dino enthusiasts, the scientific community recently confirmed the Brontosaurus was indeed its own species. One look at Dustin’s Brontosaurus hoodie and thunder lizard lovers came out of the woodwork to demonstrate their devotion. The museum integrated the strategic hashtag #thunderlizard into social media messaging immediately, catering to its core audience.

Create an Emotional Connection

While Dustin Henderson may not have been Stranger Things’ intended hero, he became one of the most celebrated characters of the show. A smart and silly smartass, his nerdy awkwardness made him relatable—especially to anyone who grew up in the 80s or those who struggled to navigate their tween years. There is something really powerful about seeing yourself in someone else and that emotional connection is a key piece of going viral. The museum piggybacked on Dustin’s popularity, connecting with Netflix immediately so they could officially publish images connected to this lovable underdog.

Act When the Timing Is Right

The day of the show’s release, viewers around the world did what Netflix has done such a great job influencing us to do: We changed into our comfy clothes, grabbed our snacks, and got down to binge watching. And when Dustin appeared in the thunder lizard sweatshirt during the very first episode, the millions of people who were actively streaming began to comment about it online; they wanted to know how they could get their hands on one just like it. The Science Museum’s social media team continuously monitors its social feeds so they were able to react quickly—they were on top of the situation as it happened.

Join the Conversation

The thing I most often tell business owners and authors is that social media is intended to facilitate two-way conversations between an organization and its audience. Developing and implementing a content plan will only take you so far. If you want to create raving fans and loyal brand advocates, genuinely interacting with your audience is a must. The museum did not sit idly by as the buzz began, they were actively engaged in the conversation from get-go. And they were authentic and transparent in ongoing communication about product availability and website snafus, which is key to building a lasting relationship with your audience.