William Heirens News Today

For the morbidly curious.

Did you know that two of the world's worst and most famous serial killers were from Illinois?

For decades, criminologists and true crime documentaries have attempted to understand what causes serial killers to commit the atrocities they do.

For decades, criminologists and true crime documentaries have attempted to understand what causes serial ki...

(CNN) — For decades, criminologists and true crime documentaries have attempted to understand what causes serial killers to commit the atrocities they do.

For decades, criminologists and true crime documentaries have attempted to understand what causes people to become serial killers. CNN spoke with three forensic psychologists and serial killer experts to learn more.

(CNN) — For decades, criminologists and true crime documentaries have attempted to understand what causes serial killers to commit the atrocities they do.

For decades, criminologists and true crime documentaries have attempted to understand what causes people to become serial killers. CNN spoke with three forensic psychologists and serial killer experts to learn more.

By Alaa Elassar, CNN

(CNN) — For decades, criminologists and true crime documentaries have attempted to understand what causes serial killers to commit the atrocities they do.