Trey Barrineau

USA TODAY

An incomplete Alfred Hitchcock documentary on the Holocaust that includes some "truly shocking footage" is being finished and restored by London's Imperial War Museum and will air on British TV in 2015, The New Zealand Herald reports.

The release will coincide with the 70th anniversary of the liberation of Europe at the end of World War II. A making-of documentary, Night Will Fall, is being produced in conjunction with the film, and both will be released in theaters as well.

The original documentary is titled Memory of the Camps. It was filmed in 1945 but was never released because of production problems and political pressures, according to PBS' Frontline, which aired an unedited, incomplete version in 1985 after a researcher found it in the Imperial War Museum's vaults. The new version, which doesn't yet have a title, is being digitally restored and will include footage that was missing from the 1985 version.

Hitchcock collaborated on the documentary with friend and future business partner Sidney Bernstein, who said the famed director refused to be paid for his work. PBS says Hitchcock's role was to "shape the way the documentary was presented." Later, while reviewing the footage shot by British Army cameramen, the master of the macabre was so traumatized that he "stayed away from Pinewood Studio for a week," according to The New Zealand Herald.

The finished documentary could be equally shocking for today's audiences.

"Judging by the two test screenings we have had for colleagues, experts and film historians, what struck me was that they found it extremely disturbing," Imperial War Museum curator Toby Haggith tells The New Zealand Herald. However, Haggith also says it's "both an alienating film in terms of its subject matter but also one that has a deep humanity and empathy about it."