Chapter Titles:
- 1. The Voice From the Void
- 2. The Queen of the Night Riders
- 3. The Invisible Enemy
- 4. The Fatal Message
- 5. The Trackless Trail
- 6. The Radio Riddle
- 7. The Crimsom Clue
- 8. The Doorway of Disaster
- 9. When Time Stood Still
- 10.Riding the Whirlwind
- 11.The Capsule of Oblivion
- 12.The Hoofs of Horror
Cheapskate producer Nat Levine scored a windfall by being able to cast Harry Carey and Edwina Booth, who just came off starring in the major MGM hit Trader Horn. Booth was still recovering from a serious bout with a tropical disease contracted in Africa while filming this serial.