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.)

• P. E. P.
• BFI
• H. Agar Lyons
• Fred Paul
• Wally Patch
• Fred Rains
• Evelyn Arden