Whereas Bong Joon-ho’s Memories of Murder used a criminal investigation in dictatorial South Korea to suggest endemic figurative impotence, Na Hong-jin’s spiritual successor makes such flaccidness literal vis-à-vis its sexually frustrated, prostitute-slaughtering serial killer (Ha Jung-woo). Such unfavorable comparisons dog Na’s debut, a convoluted procedural that goes to brutal lengths to comment on the perversities of human nature and law enforcement, and yet undercuts its mournfully gloomy worldview with hectic humor. In Seoul, cop-turned-pimp Joong-ho (Kim Yun-seok) searches for two of his missing call girls and discovers they’ve been hammer-and-chiseled to death by a nondescript loner. Momentarily bucking genre conventions, the lunatic quickly confesses, shifting the focus to the inept quests for evidence by both a cartoonish police force and Joong-ho, who develops a softy’s heart while caring for the daughter of his abducted hooker. Self-serving motivations soon trump concerns for justice, but the pessimism of Na’s slick debut rings false. A late-act tragedy drenched in bloodlust slow-mo epitomizes the film’s poseur bleakness, with its treatise on individual and institutional amorality sabotaged by broad-stroke characterizations and a knotty narrative too reliant on twin modern-day horror tropes: preposterous decision-making and lousy cell phone service.