

A young girl is kidnapped by a serial killer. The serial killer uses manholes to kidnap and kill his victims. The young girl's older sister tries to save her before it's too late.
Practical Effects
Repulsive sewer sets you'll smell through the screen.
Acting
Jung Yu-mi's desperate physicality sells every bruise.
Direction
Shin Jae-Young makes concrete tunnels feel endless.
Director
Shin Jae-Young
Trivia, insights & behind the scenes
Released during Korea's ongoing reckoning with real serial killers like Yoo Young-chul, the film taps into genuine urban anxiety about invisible predators beneath modern Seoul's gleaming surface. SpoilerLevel: FREE
Kim Sae-ron was only 14 during filming, making her terror scenes uncomfortably authentic — she later called it her most physically demanding role until her 2014 breakout in A Girl at My Door. SpoilerLevel: FREE