Los Angeles, California - The new horror movie Smile dominated the box office this weekend and at least part of that success is thanks to a viral marketing campaign.

To promote the film, Paramount sent actors into the crowds of several live events, primarily Major League Baseball games. The actors stood in the background of the action with a disturbing smile frozen on their faces.

Smile features a supernatural force that possesses people and forces them to do terrible things while grinning in the same creepy manner as the actors did.

The horror movie, which stars Sosie Bacon, dominated the box office on its opening weekend, scoring the top spot with $22 million in ticket sales.

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Smile may owe much of this success to its unusual marketing tricks.

Baseball fans were collectively freaked out by the smiling actors placed in the crowds last week. One viral video, taken during the Oakland Athletics and New York Mets matchup on September 23, showed one of the actors in the first row of the crowd smiling straight into the camera during the television broadcast. Smiling actors were also spotted at New York Yankees and Los Angeles Dodgers games.

One TikTok with over 3 million views features a Smile actor grinning amid a swarm of fans, some cheering while others giving hilariously horrified looks to the cameras.

And it wasn't just the viral posts that spread the word. TikTok users also made videos responding to the creepy campaign, praising its innovation and creativity.

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In addition to the actors, the marketing campaign also included a website created specifically for the film called smilesightings.com.

The website features the tagline, "Once you see it, it's too late," and calls on visitors to "Report this smile." Visitors can submit photos of "real world" smile sightings or share a selfie using a Smile Snapchat filter. If you stay on the page for more than a few seconds, you'll be met with a terrifying jump scare.

Smile director Parker Finn revealed that he wasn't entirely sure the marketing tactic would even work. "I've got to say, Paramount marketing has been very clever with some of the tricks they've had up their sleeves for this film," Finn said, per Entertainment Weekly.

"This is something that had been discussed a little while back and we were all kind of like crossing our fingers that somebody might notice."

Finn had little to worry about, as the film's box office success has proven. This is also not the first time that marketing teams have taken a similarly daring route.

The found footage flick The Blair Witch Project gained traction through a clever promotional tactic that set out to confuse potential audiences. The marketing team posted missing person posters featuring the characters on college campuses, created a website to explain the urban legend surrounding the Blair Witch, and wrote messages on online forums drawing attention to the legend and the missing persons. The campaign was massively successful, with the movie earning $248.6 million at the box office on a budget under $1 million.

Smile's similar infiltration of the real world shows the lasting impact of The Blair Witch Project's advertising over 20 years after its release. By placing the actors at live events, Smile expertly brought the strategy into the age of social media, targeting both older demographics who were likely watching the MLB games live on TV, as well as younger audiences who would respond to the photos and videos of the actors shared online.

If Smile's success is any indication, we should prepare for even creepier – and even more real – horror movie marketing campaigns to come.