Errol Morris' film is built around the theory that Charles Manson learned mind-control techniques from the CIA. But guess what? There's no evidence.

Tom O'Neill was commissioned by Hollywood-centric film magazine Premiere to investigate exactly what had - by then - happened a mere 30 years earlier, when a small-time criminal, Charles Manson, was unveiled as the mastermind behind one of the most brutal and defining crimes of the 20th century.