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.
Will Hay
as Prof. Davis
John Mills
as Bobby Jessop
Basil Sydney
as Costello
Felix Aylmer
as Crabtree
Thora Hird
as Joyce
Henry Hewitt
as Prof. Davys
Owen Reynolds
as Harman
Frank Cellier
as Innsbach
Joss Ambler
as Sir John
Frank Allenby
as Onslowe
Margaret Halstan
as Matron
Barbara Valerie
as Sister Spooner
