Poltergeist: The Legacy

The Thirteenth Generation (1x15)

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During the 17th Century a suspected witch is 'tested' by being dunked in water, as she goes to her death she curses the next thirteen generations of the Witchfinders family. While guest lecturing at a Boston University Derek gets involved in a series of murders/deaths that seem to involve the same family and could be connected to the long rumoured curse.