Schwalmstadt Maximum Security Prison in Germany. Locked up behind the walls of this 12th-century castle are 188 of Germany's worst offenders. The prison is a fortress surrounded by a moat, and houses dangerous criminals, many of whom attend intense therapy sessions.

The tropical island of Mauritius is home to Melrose maximum security prison, where 800 of the country's worst drug smugglers, sex offenders and murderers are locked up. Every convict is watched day and night and even the smallest infraction is met with extreme punishment.

Lesotho's Maseru Central Correctional Institute in Southern Africa holds the country's most dangerous and disturbed criminals. Shockingly almost half the inmates are doing time for rape. The culture of sexual violence in Lesotho has deep roots in society. Women are taken as secondary citizens in their culture. And sexual aggression continues inside the prison.
In this episode, Raphael Rowe will spend a week locked up in this African prison surrounded by sex offenders.

(Click CC for subtitles) Hector Berrellez's informants give him ground breaking evidence - first-hand, eyewitness accounts of Kiki's kidnapping, torture, and murder. He learns the incident took place in a cartel hacienda where high-level Mexican government officials were present, along with a mysterious Cuban. They also reveal the cartel and governments attempts to cover up the crime.

Michelle McNamara reflects on the 1984 murder of her childhood neighbour Kathy Lombardo, which she credits with planting the seed for her lifelong fascination with unsolved crimes. Michelle really wanted this child and wished to get her murderer caught. The story of the victims has to be told.

In 1979, law enforcement is thrilled when the East Area Rapist attacks abruptly stop in Northern California. But in reality, the East Area Rapist had only moved 400 miles south, to commit a number of gruesome murders in the Santa Barbara area, where he would become known as the Original Night Stalker. Michelle McNamara ultimately came up with the name 'Golden State Killer' cause he terrorized up and down the state.
Michelle starts to write a true crime book that would transcend the genre because the way she humanized all of the victims.