Supernatural Sisters

Heather and Dana are sisters. One day their father unemplainably dies. Their mother vanishes into thin air. One day while they were packing up their dads stuff they came across a book they had never seen before. It had their fathers initials on the front of it.

Opening up the book the sisters saw some weird looking ancient symbols and Latin words on them. Was their dad part of some weird magic cult or some kind of supernatural hunter?
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