EXCLUSIVE: Fox is exploring the gruesome murders carried out by Charles Manson’s ‘family’ in a new Liev Schreiber-narrated documentary special based on a vault of unseen footage of the cult. I hear that the broadcaster has ordered two-part Inside The Manson Cult: The Lost Tapes from Naked Entertainment.

The documentary is a retelling of the Manson story using original 16mm footage that was found in the archives of Robert Hendrickson, the filmmaker behind Oscar-nominated doc Manson who died in 2016. The series will look at how the members, who carried out a number of grisly murders, including the brutal attack on Sharon Tate, went from peace-loving hippies to mass murderers.

The two-parter goes inside Spahn’s Ranch, where the Manson cult lived, to offer an intimate and terrifying look into America’s most murderous group. The special will feature rare photos and new and archival interviews with former Manson cult members, such as Catherine “Gypsy” Share and Dianne “Snake” Lake, as well as key people involved in the Manson case, including prosecutor Stephen Kay and FBI criminal profiler John Douglas.

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Directed by Hugh Ballantyne (Finding Jesus), the doc will explore how Manson orchestrated the murders and encouraged a group of mostly young, middle class women to carry out the killings, which he hoped would be blamed on the Black Panthers and lead to a race war.

The doc is produced by Naked Entertainment, the FremantleMedia-backed UK and U.S. production company set up by Simon Andreae, who was Executive Vice President, Alternative Entertainment at Fox Broadcasting between 2013 and 2015. It is the company’s first major U.S. network order, having recently made a number of series for Viacom’s Channel 5 and Channel 4 in the UK. Inside The Manson Cult: The Lost Tapes is exec produced by Andreae, Ballantyne, Richard Dale, Allan Gaba and Dean Egnater. It is understood to have been co-produced in association of British broadcaster ITV.

The special is the latest Charles Manson-related project to emerge as the 50th anniversary of the cult’s most infamous murder, the killing of Tate, approaches next year. Quentin Tarantino’s forthcoming movie Once Upon A Time, which stars Margot Robbie, Brad Pitt and Leonardo DiCaprio also mines this world.

It is the latest Charles Manson project developed by Fox; in 2014, the broadcaster developed a scripted series from American Psycho author Bret Easton Ellis and horror director Rob Zombie that was set a year before the Manson family’s murder spree in 1969. However, it never made it to air and was ultimately trumped by NBC’s David Duchovny-fronted series Aquarius, which mined similar territory.