The Tomato giveth, and the Tomato taketh away. And lo, the gospel of RottenTomatoes.com has Hollywood popping Klonopin and yanking out its hair more than ever as summer movie season gets going.

Take the cautionary tale of Baywatch and Pirates of the Caribbean: Dead Men Tell No Tales, two films predicted by pre-release tracking to do boffo box office over Memorial Day weekend.

But after their dismal “freshness” ratings hit Rotten Tomatoes’ all-powerful Tomatometer—which assigns a numerical score to a given film based on a round-up of critical reviews—the Rock-starring lifeguard comedy promptly flopped, and the fifth installment of Disney’s long-running Johnny Depp franchise hauled in a “soft” $46 million—the lowest opening for a Pirates movie in 14 years.

“Insiders close to both films blame Rotten Tomatoes, with Pirates 5 and Baywatch respectively earning 32 percent and 19 percent Rotten,” Deadline reported. “The critic aggregation site increasingly is slowing down the potential business of popcorn movies.”

On the flip side, when it came to Warner Bros.’ Wonder Woman, the film’s “Certified Fresh” designation became an all-but-inescapable talking point—its 93 percent Rotten Tomatoes rating became an actual headline. And that helped the superheroine thriller shatter the glass ceiling of tracking expectations of a $65 million debut, magically lassoing $103.1 million over its opening days in theaters.

Video: A Brief History of Wonder Woman

Launched on a lark in 1998 by Web designer Senh Duong to catalogue reviews for Jackie Chan kung-fu flicks, Rotten Tomatoes has come to dominate the cultural conversation surrounding new movies and fundamentally change the calculus of putting butts in seats. It’s particularly, terrifyingly powerful among teens and 20-somethings who, as recently as five years ago, relied more often than not on “Bro, you gotta see this”-style word of mouth than any sort of professional critic appraisals to make their multiplex picks.

“Moviegoers love trailers. They pay attention to the TV spots. But Rotten Tomatoes is like the truth serum on the entire [promotional] campaign: are all the things you’re telling me about the movie true or not?” says Jon Penn, chief executive of the movie research firm National Research Group (NRG), which has tracked Rotten Tomatoes’ influence on audience behavior since 2010. “These scores are almost like a lubricant one way or the other. If it’s good, it helps you more than it did in the past. But if it’s bad, it hurts you even more.”