In Chaos: The Manson Murders, Oscar-winning director Errol Morris delves into the shadowy and complex narrative of the Manson family murders. The documentary, out now on Netflix, explores the darkest corners of recent history to unpack the potential conspiracy surrounding the killings. Unraveling a tangled tale involving the CIA, LSD, the JFK assassination, the Manson family, and Los Angeles attorney Vincent Bugliosi, the prosecutor whose 1974 bestseller Helter Skelter chronicled the Manson trial, the film casts doubt on the official story of the 1960s’ most infamous killing spree.

The documentary invites viewers to question the roles of well-known players and powerful institutions alike in a thought-provoking exploration of the tumultuous era’s cultural and political undercurrents.

“I’ve found myself trapped in a number of different true-crime stories, and the Manson murders are peculiar,” Morris told Netflix. “You could encapsulate the mystery in just...