The Mark of a Serial Killer, The Grim Sleeper

When investigators set up an undercover operation, the hunter soon becomes the hunted.

After multiple men are discovered brutally murdered, investigators determine that each victim was last seen with a handsome stranger they met in a bar.

Police realize they may have a killer stalking the area nightclub scene, one who is able to charm his victims into submission.

The search for a killer is on after multiple bodies are found in abandoned buildings.

The investigation is set ablaze when flames obliterate evidence, until police make a shocking discovery.

A killer crisscrosses the Midwest leaving a string of victims along the interstate. When investigators are hot on the highway killer's trail, the murderer suddenly changes his mark.

A cold blooded killer conceals his victim's bodies with trash, discarding them like garbage in the back alleys across Los Angeles.

A Houston killer taunts the media and authorities as he uses homemade ligatures to murder his victims.

El Paso investigators race to track down a ruthless killer that is burying his victims in shallow desert graves, dead or alive.