Unknown Serial Killers of America

When four women are found murdered across four states in a single month, police race to track down a charismatic drifter.

When a series of brutal attacks on young women terrorizes the Twin Cities, detectives are taunted by a killer who repeatedly calls 911 to confess.

A rising body count fuels a desperate hunt -- until one woman's daring escape exposes the predator hiding in plain sight.

When police discover a string of deaths at an upscale retirement community are not natural, they uncover a predator with a motive that defies reason.

Police go on a hunt across state lines to stop a calculating maniacal killer methodically checking victims off his deadly list.

Investigators launch a desperate manhunt for a long-haul trucker whose killing spree leaves a trail of victims across state lines.

After a series of victims are found in upstate New York, posed and stabbed beyond recognition, police pursue a maniacal suspect.

Bodies of gay men appear along I-95, each marked by the same chilling signature.