A US newsman and a British entomologist spy on germ-warfare research in a mythical country.

Margaret Lockwood
as Frances Gray

Dane Clark
as Bill Casey

Marius Goring
as Commandant Anton Razinski

Naunton Wayne
as Mr. Hedgerley

Wilfrid Hyde-White
as Mr. Luke

Eugene Deckers
as Alf

Olaf Pooley
as Detective-Interrogator

Gladys Henson
as Attendant

Paul Hardtmuth
as Priest

Michael Hordern
as Lab Director Owens
CinemaSerf
Margaret Lockwood is a scientist ("Frances Gray") who is asked by the British government to travel to the Balkans to discovers whether the communists there are trying to weaponise the humble fruit fly! Initially nervous, she takes courage from a radio serial that she listens to for her young nephew,...