After director Cliff Owen injured his back so badly that he was unable to work, producer Aida Young was forced to step in and direct the final few days of the film's location shoot.
Although planned as a sequel to Hammer's La Déesse de feu (1965), a last-minute rewrite of the script removed all connections to the earlier movie. This now plays more as a remake of "She" with an immortal man in place of an immortal woman.
Ursula Andress starred in La Déesse de feu (1965) but turned down the chance to star in this sequel.
After Ursula Andress turned down repeating the role she had created, model Samantha Jones, Britt Ekland (Peter Sellers' wife) and Barbara Bouchet were also considered for the role.
Susan Denberg was announced as a replacement but eventual newcomer Olga Schoberová was cast instead.