Opening narration: "Is violence born in the heart, or in the mind? If we must kill to protect ourselves, what will that do to our souls?"
When Detective Terry Russo is called to investigate a double murder, it looks like an open and shut case. However, as Russo questions the man caught fleeing the murder scene, she discovers to her horror she may be solving not one crime, but possibly hundreds. Gerard make the improbable claim that he is an alien energy being who can move from one human host to another.
Meanwhile, he tells Russo that he is a kind of cop who has been tracking another energy being like him for centuries - a psychopath responsible for some of history's most infamous crimes. When he causes Russo to see key events to support these claims by instilling visions in her mind, the detective reluctantly begins to believe him. Gerard contends that the target of his hunt killed his own host body and slipped into someone near the scene of the crime. It doesn't take the homicide detective long to find out who.
Closing narration: "In the struggle between life and death, sometimes survival is not the only way to win."
original airdate--August 20,1999
music: theme song "Outer Limits" by Mark Mancina and John VanTongeren