What to read after Dark Invasion?

A gritty, high-energy tale of German espionage and terror on American soil during World War I - and how it was uncovered. New York City, 1915: as World War I rages in the battlefields of Europe, a covert war is taking place in America. When the Germans find out that the supposedly neutral United States have been supplying goods to Britain and other Allied powers, they implement a secret plan to strike back. Franz von Rintelen, an aristocratic German with connections in American banking, arrives in New York to set up a spy network. This team of saboteurs - including an expert on germ warfare, a Harvard professor, and a brilliant, debonair spymaster - devise a series of 'mysterious accidents', involving explosives and biological weapons, to bring down targets such as ships and factories, and even captains of industry such as JP Morgan. As the authorities get wind of this, New York police inspector Tom Tunney, head of the city's bomb squad, is assigned to stop them. Assembling a team of operatives, he begins a hunt for the conspirators. But as Tunney heads deeper into a labyrinth of deception, he realises that the Germans' plan is far more complex and dangerous than he had suspected.What develops is a tense cat-and-mouse battle between the American cop, with his team of novice spy-chasers, and the German spy, with his plan to wage a secret battle to disrupt American trade and affect the course of the war. In the tradition of bestsellers such as Erik Larson's In the Garden of Beasts, this is a riveting real-life thriller about a critical period in world history. It reveals the little-known, incredible story of how American naivety and German ruthlessness placed the United States, and the Western world, in mortal peril.