Deliver Us from Evil

When a frightening wave of violence sweeps through New York City, troubled cop Sarchie fails to find a rational explanation for the bizarre crimes. However, his eyes are opened to a frightening alternate reality when renegade Jesuit priest Mendoza convinces him that demonic possession may be to blame for the gruesome murders. Together, they wage a valiant supernatural struggle to rid the city of an otherworldly evil.

You haven't seen true evil.