10 horrific, real-life murder mysteries that have never been solved, including;
Zodiac : America's most enigmatic killer. Zodiac killed at least 5 and carried on an extended letter writing campaign, taunting the San Francisco police and daring them to try and stop him.
The Mad Butcher of Kingsbury Run : Not even celebrated crime fighter Eliot Ness could put an end to the Butcher's deadly murder spree.
The Monster of Florence : Il Mostro stalked the lover's lanes and campsites around Florence for over two decades, killing and harvesting body parts.
Jack the Ripper : The granddaddy of all serial killers. Saucy Jack terrorized London's East End for three blood-drenched months in 1888, leaving a trail of mutilated corpses in his wake.
The Axeman of New Orleans : A homicidal maniac who reeked havoc on New Orleans during the early part of the 20th century and seemed to bear a particular grudge against Italian grocers.
The Boston Strangler : Albert De Salvo took the fall while the real Strangler, slayer of as many as 13 women, walked free.
The Frankford Slasher : A lethal ripper who stalked the streets of Philadelphia during the 1980's killing and mutilating his victims.
Bible John : A Bible-sprouting psychopath who raped and strangled three young women in 1960's Glasgow. But was he eventually caught for another murder?
The Servant Girl Annihilator : A deadly serial killer who started by targeting Austin's servant population, before setting his sights on the city's social elite.
Jack the Stripper : The Stripper bamboozled London's police in the 60's committing a series of strangulation murders that have never been solved.