Helen MacInnes

Ian Ferrier, an employee of the United States Space Agency, vacationing in the Mediterranean, finds himself involved with the security of nations when he stumbles onto an assassination conspiracy in Spain.

English girl Sheila Matthews' innocent holiday to Poland becomes a nightmare when the German Army invade in the summer of 1939. Working for the Polish underground as a double-agent, she plays a dangerous game, and is soon suspected by the Germans. Forced to flee to the forest and hunted by a ruthless German officer, she must rely on the dashing Captain Adam Wisniewski to help her home.

Richard and Frances Myles are preparing for their annual European summer vacation in 1939 when they are visited at their Oxford college by old friend Peter Galt, who has a seemingly simple job for them. But in the heightened atmosphere of pre-war Europe, nobody is above suspicion; in fact the husband and wife are being carefully monitored by shadowy figures. Soon the couple are racing across Europe and must use all their ingenuity to stay one step...