The two-hour special MANSON premieres on September 7 at 9pm ET/PT on HISTORY. Shortly after midnight on August 9, 1969, a car pulled up to actress Sharon Tates sprawling Benedict Canyon home. As the driver, Linda Kasabian, stood guard outside, three of her family members committed one of the grisliest mass murders in American history. Forty years later, HISTORY presents a chilling drama-documentary featuring exclusive, first-hand testimony from Kasabian, as well as interviews with Vincent Bugliosi, the chief prosecutor in the case and author of Helter Skelter: The True Story of the Manson Murders; family member Catherine Share, aka Gypsy; and Debra Tate, Sharon Tates sister. The two-hour special MANSON premieres on September 7 at 9pm ET/PT on HISTORY.