The true story of German secret agents engaged in a campaign of subversion and terror in the United States before and during World War I.

Many believe that World War I was only fought "over there," as the popular 1917 song goes, in the trenches and muddy battlefields of Northern France and Belgium—they are wrong.

There was a secret war fought in America; on remote railway bridges and waterways linking the United States and Canada; aboard burning and exploding ships in the Atlantic Ocean; in the smoldering ruins of America's bombed and burned-out factories, munitions plants, and railway centers; and waged in carefully disguised clandestine workshops where improvised explosive devices and deadly toxins were designed and manufactured. It was irregular warfare on a scale that caught the United States woefully unprepared.

This is the true story of German secret agents engaged in a campaign of subversion and terror on the American homeland before and during World War I.