
Miriam Monroe and John Conrad are two young scientific workers who, independently of each other, have discovered a chemical called exonite. Miriam discovered it while searching for a cure for cancer, while Conrad used it as a basis for a powerful explosive.
Miriam Monroe
John Conrad
Albert Bernard (as Harry S. Northrup)
Randolph Monroe

Bradford Duncan
Eric Johansen
Prof. Poole (as Fred C. Truesdell)
Maj. Gen. Foster (as Redfield Clark)
Williams
Capt. Herbert