Kane Parsons’ “ Backrooms ” has already shattered the record for A24 ’s best opening weekend. Adapted from Parsons’ viral YouTube series, “Backrooms” earned $38 million domestic on Friday from 3,442 theaters, and is projected to gross $85 million to $90 million through the weekend. That’s more than triple the previous record holder, Alex Garland’s thriller “Civil War,” which earned $25.5 million in 2024 to claim the title of A24’s best debut. 'The Mandalorian and Grogu' Gets Divided First