The director of Universal's big Jessica Chastain horror movie got his break by pranking his friends on a Zoom call, then turning the prank into a $100,000 feature in 12 weeks. April 2020, lockdown. Rob Savage was an out-of-work British director killing time on a Zoom with actor friends. Mid-call he "heard noises" in his attic, carried his laptop up to investigate, and hit them with a homemade jump scare so convincing one friend almost called the police. He posted the 2-minute clip and it blew…