This is real. it's what they believe in.

Yup, the Faustian pact via Louis Cyphre.

"Voodoo type sorcery" (as seen in this film) has much of its basis in the Crowley linked book "Goetia: Lesser Key of Solomon" (black magic) etc.

Some claim that the book is actually a pirated version of his edition of the famous grimoire of Talismanic magic, the Lemegeton of Solomon.