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.

Yankee charter pilot Morris inadvertently finds himself in the midst of thieves who have purloined a costly antique jade figure from an exhibit. He tracks the thieves to Battersea, where he rescues the fair Germaine from their unsavory clutches, and the Buddha boosters gain only jaded justice.