Lieutenant Commander John Byrne of the Naval Secret Service and his partner Pvt. Bill Riggers chase criminal Dr. Sin Fang, who is desperate to find a lost sacred seal. (The fifth and only surviving episode of a six-part serial about an evil mastermind inspired on Sax Rohmer's Dr. Fu Manchu.)
Movie tag line: "Tagline Not Available"
Production companies:
Character: Dr. Sin Fang
Character: Lt. Comdr. John Byrne R. N. of the N. S. S.
Character: Private Bill Riggers
Character: Professor Harbray
Character: Betty Harbray