Night of the Demon (1957)

American professor John Holden arrives in London for a conference on parapsychology only to discover that the colleague he was supposed to meet was killed in a freak accident the day before. It turns out that the deceased had been investigating a cult lead by Dr. Julian Karswell. Though a skeptic, Holden is suspicious of the devil-worshiping Karswell. Following a trail of mysterious manuscripts, Holden enters a world that makes him question his faith in science.
Jacques Tourneur, Basil Keys
Dana Andrews, Peggy Cummins, Niall MacGinnis, Athene Seyler, Liam Redmond, Peter Elliott, Ewan Roberts, Reginald Beckwith, Rosamund Greenwood, Brian Wilde, Maurice Denham, Richard Leech, Lloyd Lamble, Peter Hobbes, Charles Lloyd Pack, John Salew, Janet Barrow, Percy Herbert, Lynn Tracy, John Harvey
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