A professor teaching at a correspondence school discovers that a Nazi agent is trying to prevent a trade treaty being signed between England and South America.
as Prof. Davis
as Bobby Jessop
as Costello
as Crabtree
as Joyce
as Prof. Davys
as Harman
as Innsbach
as Sir John
as Onslowe
as Matron
as Sister Spooner
as B.B.C. Interviewer
as Male Nurse
as Station Master
as Ticket Collector
as Sister at Nursing Home
as Hotel Receptionist
as B.B.C. Producer
as Hospital Nurse
as Butcher's Boy
as Miss Rudge
as Journalist
as Train Passenger
as Mrs. Webster
as Ministry Receptionist
as Nurse
as Porter
