- Robert Kanigher
- Carmine Infantino
- Frank Giacoia
- The Flash [Jay Garrick]; Dale Thomas (newspaper publisher); Dr. Maria Flura; Graves (press man); Jim Ronson (newspaper reporter); Mr. Browne (sailor)
- Newspaper publisher Dale Thomas finds the body of a former fellow explorer in the newspaper presses in his plant. This man had once discovered a secret city in the jungles of the Amazon, and Thomas, accompanied by the Flash and Dr. Flura, are determined to find that city and rescue reporter Jim Ronson, no matter what the cost!
Credits by Craig Delich.
Modified synopsis by Craig Delich.