Warning: This post contains spoilers for Backrooms , now in theaters.

When failed architect and struggling furniture store owner Clark ( Chiwetel Ejiofor ) discovers a mysterious portal in the basement of his strip mall warehouse that leads to a sprawling, maze-like dimension of drab, yellow-wallpapered rooms, he becomes obsessed with exploring the nightmarish realm. Unfortunately, he's very much not alone in this liminal labyrinth.

Backrooms , directed and co-written by 20-year-old YouTuber-turned-filmmaker Kane Parsons, follows Clark as he drags his assistant manager Kat (Lukita Maxwell), her boyfriend Bobby (Finn Bennett), and, eventually, his therapist, Dr. Mary Kline (Renate Reinsve), down the rabbit hole of this terrifying alternate reality with him. It's a slow-burn horror that relies on the unsettling nature of that uncanny limbo to build atmospheric dread before ratcheting up to true cosmic horror.…