Red Lights is a thriller in which suspense depends on keeping both viewer and protagonist teetering, in the face of the unexplained, between rational agnosticism and faithful credulity. By the finale, however, it has become unbelievable in a way that can't possibly have been intended. Professional skeptic Dr. Margaret Matheson (Sigourney Weaver) and her assistant, young physicist Dr. Tom Buckley (Cillian Murphy), are investigating the case of Simon Silver (Robert De Niro), a blind celebrity psychic who emerges from retirement for a comeback tour. He's Matheson's bête noire because she could never satisfactorily explain away his seemingly fatal powers. But there's no detectable motivation for Silver, neither for his long retreat from the public eye nor for his sudden messianic re-emergence, and a lengthy sequence where Buckley trails Silver is only an excuse for an excursion into Lynchian interior decor and Spooky Black Folks. Although Red Lights' most effective scenes make the viewer party to the rush of cracking codes and unmasking frauds, Cortés abandons this pattern in the last act for a finale that sacrifices his film's integrity on the altar of a confusing, sub–M. Night Shyamalan twist that is more likely to leave viewers groaning than appreciatively shaking their heads at being taken in.