Kim Richards, Ike Eisenmann, and Denver Pyle reprised their roles as Tia, Tony, and Uncle Bené from Die Flucht zum Hexenberg (1975). This movie was also directed by the same director, John Hough, as well as having many of the same technical and production crew.
First of two collaborations of director John Hough and Bette Davis. They re-teamed for another Disney movie, Schreie der Verlorenen (1980).
Bette Davis agreed to do this movie because it was a movie her grandchildren could watch. Also, Davis had three people tending to her on the set throughout the shooting of this movie.
Second of five "Witch Mountain" movies. This sequel was released three years after Die Flucht zum Hexenberg (1975). Later came the second sequel, Beyond Witch Mountain (1982), then a television remake of the original, Die Flucht zum Hexenberg (1995), then another remake, Die Jagd zum magischen Berg (2009).
This movie was unique in its casting of two suspense and horror movie genre legends, Bette Davis and Sir Christopher Lee, as cohort villains. This movie was the only theatrical movie where the pair were teamed together.