Dark Danger by Malcolm Saville.
 
This is the third of the new series of Secret Service thrillers featuring Marston Baines and his three undergraduate friends. It is a splendid and worthy sequel to Three Towers in Tuscany and The Purple Valley. This time the scene is set in Venice and Rome where a sinister gang is plotting international blackmail.
 
Dark Danger is not only an intensely exciting, fast-moving story but it offers something unusual. The scene against which it is set is vividly described and obviously well known to the author, but what is more important is the way in which the conflict between good and evil—of the forces of light and the powers of darkness-is shown through the action of the characters.
 
Malcolm Saville has proved himself to be a great story teller. This book places him firmly in the top rank of those writers for young people who believe their audience will appreciate more in a story than just a competent narrative.