Advertisement A good Catholic horror movie does more than exploit the dread of the devout. Like the most gifted of fire-and-brimstone evangelists, it makes that fear persuasive, sending a chill of religious terror up the aisles and down the spines of even the staunchest atheists. It makes believers out of nonbelievers, if only for a couple pea-soup-drenched hours. The Unholy, which arrives this Easter weekend to tempt the most god-fearing and least virus-fearing back into theaters, plainly aspires to a canon of Hollywood nightmares pulled from Sunday school curriculum. Yet despite its earnest warnings about a wolf draped in sheep’s clothing, the film never taps into the spooky power of the scripture’s most enduring scare tactics. This is the flimsiest of hokum, possessing all the gravity of a bible salesman hocking his wares outside the subway.