The Most Terrifying Serial Killers Who Were Never Caught

We know the true names of several vicious and frightening serial killers, names which have entered into our collective cultural consciousness—infamous names like John Wayne Gacy, Ed Gein, Ted Bundy, Jeffrey Dahmer, Henry Lee Lucas, Ottis Toole, Dennis Rader (AKA BTK), and Gary Ridgeway (AKA The Green River Killer).

But what of those killers out there who, like Rader and Ridgeway, have fairly infamous killer nicknames, but whose true identity remains a mystery? Arguably, these killers are far more terrifying than the names listed above because we still know very little about them, least of all their real names. From world-renowned figures like Jack the Ripper and the Zodiac Killer, to lesser-known, but no less horrific murderers like Servant Girl Annihilator and the Monster of Florence, these unknown serial killers captivate our imaginations, and thus gain access to our worst nightmares.