This movie was released under at least three different titles in its native Turkey: "Yilmayan Seytan" ("The Indomitable / Undaunted Devil") , "Ölümsüz Seytan" (literal translation is "The Immortal Devil", but foreign distributors chose "Deathless Devil" instead) , and "Bakirbas" ("Copperhead").
When altered for American release, the stars became known as Kunt Brix, Ruth Taylor, and Jack London. The director became known as Robert Gordon.
Kunt Tulgar has stated in an interview that their original vision for Dr. Satan's robot was a humanoid, in the shape of a regular human being. The plan was that the skin on the humanoid's arm would be peeled off in one fight scene, and it would reveal cables and machinery parts underneath (this was twelve years before The Terminator (1984)). However, budget limitations forced them to end up with a cardboard box robot.