A U.S. agent attempts to track down a spy ring working to destroy the Panama Canal.
| Actor | Role |
|---|---|
 Leon AmesMaj. Phillip Waring | Maj. Phillip Waring |
 Charlotte WyntersHelen Lane | Helen Lane |
 Adrienne AmesLia Maing | Lia Maing |
 Richard LooTommy Young | Tommy Young |
 Weldon HeyburnMurdock | Murdock |
 Abner BibermanArlie Johnson | Arlie Johnson |
 Philip AhnSun | Sun |
 Don 'Red' BarryLoring | Loring |
 Frank DarienSam | Sam |
 Gerald MohrPilot | Pilot |
 Sidney MillerJimmy | Jimmy |
 Wilhelm von BrinckenMarlin (as William von Brincken) | Marlin (as William von Brincken) |
| HHugh McArthurLt. Everett | Lt. Everett |
 J. Scott SmartEli Maing | Eli Maing |
 Paul McVeyBaird | Baird |
| PPhilson AhnKhantow | Khantow |
 Harry C. BradleyClerk | Clerk |
 Lew KellyCaptain Lacey | Captain Lacey |