Since the early ’80s, HBO has established itself as a master of storytelling, not just through original dramas and comedies, but also through compelling docuseries that dissect real-life events with unflinching depth. In the realm of true crime, HBO excels at revealing the full scope of tragedy and trauma, often leaving viewers shaken by the disturbing truths uncovered.

Over the years, HBO has produced some of the most compelling (and chilling) docuseries ever made for television, offering audiences an unflinching look at the full scope of the real-life atrocities they examine. From bizarre cults that worship a bedazzled corpse to an apathetic mortician who treats his clients like kindling, these HBO docuseries delve into real-life monsters, chilling events, and disturbing true stories that spiral into inevitable terror.

Here are a few HBO docuseries that explore the darkest corners of humanity, the most sinister sides of society, and the hidden evil that can reside in ordinary people.