As World War I erupts, a spirited young American woman on a business trip in Europe begins to sense that her stay may have stretched too long. Caught in the turmoil of a continent at war, she and other anxious travelers scramble to find a way home. Amidst the chaos, a mysterious British officer enters the scene, complicating her journey with unexpected romance and intrigue. This captivating spy thriller kicks off on a train from Calais to Paris and culminates in Gibraltar. Based on a 1915 play of the same name, this story was first adapted into a silent film in 1918 and then into a “talkie” in 1930. This was the third novel penned by Biggers, who later created six beloved Charlie Chan mysteries in the 1920s and 1930s. -- Lee Smalley