Penny and the Pownall Case

Pownall is a secret service agent who is murdered on returning from the Balearic Islands. The murderer removes a strip cartoon from Pownall’s briefcase. The cartoon features a female character called Penny. Penny is in fact the name of the model the cartoon is based upon, and she accompanies another man to the Balearics. There she becomes involved in a web of danger, but is permanently tailed by a British detective. They discover that secret codes existed in the cartoons, and that these transmitted messages about a German war criminal. Now they must catch the murderer before he catches them.