The Manson Massacre (partially found original English version of horror film; 1971)
After the infamous Manson Family murders, many attempts by exploitation filmmakers were made to cash-in, with notable examples including The Helter Skelter Murders and Slaughter (which was later re-edited into Snuff). One of these films, known as The Manson Massacre (or The Cult), was released in 1971 and was quickly forgotten soon after. It was never released on any known home media.
Years later, however, a print of the film was found, albeit in German under the title Die Tochter Des Satans, translating to The Daughter Of Satan. To this day, an English print has yet to surface, although there is an English trailer, possibly from a late 70s re-release to cash-in on the hit TV movie Helter Skelter.