The Mark of a Serial Killer, Keys to a Killer

In the summer of 1976, the NYPD are chasing a man shooting at couples in parked cars.

Police in New York race against time before he can achieve twelve killings to complete the Zodiac.

When bodies start washing up in the river a pattern emerges, and a small piece of evidence leads police to the house of a model citizen.

After months of searching police zero in on a local family man who's been living a double life that no one suspected.

A serial killer taunted Witchita, Kansas for decades with brazen letters taking credit for his horrific kills.

In the 1990's, Louisiana is terrorized by multiple serial killers.