Lonnie Franklin Jr was arrested in July 2010 after a 25 year killing spree in which it is thought he could have killed over a 100 victims, potentially making him the most prolific serial killer in history. Significantly his arrest was not the product of painstaking detective work but completely accidental, the result of a computer DNA match that linked him to a possible 20 victims. Franklin now awaits trial. Tales of the Grim Sleeper looks into how it was possible for all this to happen.