English schoolboy and his Dutch pen friend chase a diamond smuggling gang in Holland.
Tim
Piet
Annike
The Guide
Van Helder
Mrs. Van Helder
Diamond Cutter
Police Superintendent
Grandpa
Man in Blue
Dutch Thug
London Crook
Writer
Producer
Original Music Composer
Director of Photography
Editor
Assistant Director
Camera Operator
Conductor
Continuity
Director