The Great Radium Mystery (1919)
Criminals steal a radium-powered tank from an inventor. His heiress and a government agent take up the chase. 18 episode serial-1. The Mystic Stone, 2. The Death Trap, 3. The Fatal Ride, 4. The Swing for Life, 5. The Torture Chamber, 6. The Tunnel of Doom, 7. A Flash in the Dark, 8. In the Clutches