Dark invasion : 1915: Germany's secret war and the hunt for the first terrorist cell in America / by Blum, Howard, author

“…"Combining the pulsating drive of Showtime's Homeland with the fascinating historical detail of such of narrative nonfiction bestsellers as Double Cross and In the Garden of Beasts, Dark Invasion is Howard Blum's gritty, high-energy true-life tale of German espionage and terror on American soil during World War I, and the NYPD Inspector who helped uncover the plot--the basis for the film to be produced by and starring Bradley Cooper. When a "neutral" United States becomes a trading partner for the Allies early in World War I, the Germans implement a secret plan to strike back. …”