300 minutos
A variety of people are searching for a long-hidden treasure somewhere on an island. Chapters: 1. The Isle of Fear, 2. The Ghost Talks, 3. The Phantom Duel, 4. Buried Alive, 5. The Girl Who Vanished, 6. Trapped by the Flood, 7. The Cannon Roars, 8. The Circle of Death, 9. The Pirate's Revenge, 10. The Crash, 11. Dynamite, 12. The Bridge of Doom, 13. The Mad Flight, 14. The Jaws of Destruction, 15. Justice
Don Terry
Larry Kent
Gwen Gaze
Toni Morrell
Walter Miller
Carter 'The Shark' Collins
George Rosener
Capt. Samuel Cuttle
Grant Withers
Roderick Gridley
Hobart Bosworth
Dr. X
Sandra Karina
Nurse Zanya
P.J. Kelly
Prof. Gault
Yakima Canutt
Dreer (Mole-Men Leader)
William Farnum
George Brennan Westmore (Editor)
Joe Caits
Saltwater Jerry [Chs.1,4-7,13-15]
Colin Campbell
Hawkins (the Butler) [Chs. 1-3]
Dave O'Brien
Det. Jameson [Chs. 4-7]
William Royle
Paul Thorndyke [Ch.1]
Warner Richmond
Capt. Tom Stanton, alias Capt. Tom Faxton [Ch.1]