***Unpleasant big city crime drama with Martin Sheen that morphs into sorcery-oriented horror*** A widowed therapist (Martin Sheen) moves back to New York City to find himself assisting the NYPD in a series of slayings linked to a Caribbean Voodoo-like cult. Things get worse when he discovers they want his son for a human sacrifice. Helen Shaver plays his landlord and possible romantic interest. “The Believers” (1987) is an adult-oriented crime drama that gets increasingly horrific. The plot and tone are akin to “Wolfen” (1981), albeit with the brujería cult replacing the super-wolves. It’s…