Forensic Factor

Weapons are the hallmark of violent crime, tools designed to harm - or kill. Forensic science has developed a world of techniques for tracking and identifying these devices. Blood spatter, explosive residue, ballistics and trauma wounds tell crime scene investigators their deadly story.

From the tips of their ears to the soles of their feet - criminals are betrayed by the clues their own bodies leave behind. A killer's ear against a wall, his hand on a door, the path that he walks - even the slightest impressions left at the scene help crime fighters find their man.

Fire, water, earth - killers call on all the elements in their attempt to cover up their crimes. But even a body burned to ashes, sunk deep into the sea or reduced to fragments will still tell its forensic tale.

Can the sound of a suspect's voice reveal his lie? Can the crucial moment of crime, buried deep in damaged video, be revealed? Can computers isolate a guilty face in a crowd? No longer science fiction, these are the high-tech tools of the forensics trade.

How do bugs, pigs and even the weather help investigators solve crimes? From tropical Hawaii to the frigid waters of Lake Ontario, forensic experts reveal, in gory detail, the clues nature leaves behind on a human corpse.

Serial killers are often twisted geniuses; so cunning that catching them seems almost impossible. But from Jack The Ripper to those who terrify us today, their bizarre behavior is as specific as a signature. Sophisticated crime fighters map the psychological and physical terrain of multiple murderers.