Basil Dickey claimed to have written the screenplay with his brother in law Charles W. Goddard

Favorite film of Tsar Nicholas II.

Film debut of Creighton Hale.

The novel of the same name by Arthur B. Reeve was published serially in newspapers while the film was playing in theaters. It was later published in book form.

The Pathé Frères US company took over the Eclectic Film Company and renamed it Pathé Exchange Inc. in early 1915. This is why both the old Eclectic and Pathé Exchange Inc. are listed as original theatrical distributors for this title.

The titles of the fourteen chapters are:1. The Clutching Hand2. The Twilight Sleep3. The Vanishing Jewels4. The Frozen Safe5. The Poisoned Room6. The Vampire7. The Double Trap8. The Hidden Voice9. The Death Ray10. The Life Current11. The Hour of Three12. The Blood Crystals13. The Devil Worshippers14. The Reckoning

This film was selected to the National Film Registry, Library of Congress, in 1994.