This weekend was one for the box office history books.

Movie theaters across the nation were jamming with Gen Z crowds, who showed up en masse for not one but two buzzy horror films. A24’s “Backrooms” collected a jaw-dropping, record-breaking $81 million from 3,442 North American theaters in its opening weekend. That’s as ticket sales for the Focus Features breakout “Obsession” jumped again in its third frame with $26.4 million from 2,781 cinemas — and crossed the $100 million mark domestically. Both movies were directed by YouTube stars and cost nearly nothing to produce, upending conventional wisdom about the necessary components for a hit.

That original fare is ruling is especially striking at the start of summer movie season, a period that’s usually dominated by major franchises. Yet Disney’s “Star Wars” spinoff “The Mandalorian and Grogu” suffered a catastrophic 70% drop in its second weekend, signaling the property isn’t catering beyond an aging group of core fans. It landed in third place on weekend charts behind “Backrooms” and “Obsession.”

“Blumhouse-Atomic Monster has the No. 1 and No. 2 movies in the country this weekend, both made for almost no money. Theaters are packed,” Jason Blum, who produced both films through his company Blumhouse-Atomic Monster, wrote on Twitter. “What a time to be making scary movies.”