S1·E11 Doppelganger

Sam confronts inmate Arthur deRhodes (guest star Edward Albert, ""Beauty and the Beast""), a former adversary and serial slayer whom she helped put in a prison for the criminally insane years before, over a recent murder that bears striking similarities to his modus operandi. However, when another ritualistic murder occurs, Sam wonders whether the culprit could possibly be the clever deRhodes -- or a copycat killer. All bets are off when deRhodes eventually escapes, and no one is safe -- especially Sam. Robert Davi also stars.