Recruited for the operation were eight Germans who had lived in the United States. Two of them, Ernst Burger and Herbert Haupt, were American citizens. The others, George John Dasch, Edward John Kerling, Richard Quirin, Heinrich Harm Heinck, Hermann Otto Neubauer, and Werner Thiel, had worked at various jobs in the U.S.
Their mission was to stage sabotage attacks on American economic targets: hydroelectric plants at Niagara Falls; the Aluminum Company of America's plants in Illinois, Tennessee, and New York; locks on the Ohio River near Louisville, Kentucky; the Horseshoe Curve, a crucial railroad pass near Altoona, Pennsylvania, as well as the Pennsylvania Railroad's repair shops at Altoona; a cryolite plant in Philadelphia; Hell Gate Bridge in New York; and Pennsylvania Station in Newark, New Jersey. They were given a quick course in sabotage techniques, given nearly $175,000 in American money and put aboard two submarines to land on the east coast of the U.S.
Two of the Germans in New York, Dasch and Burger, decided to back out of the mission. Dasch went to Washington, D.C., and turned himself in to the Federal Bureau of Investigation. He was dismissed as a crackpot by numerous agents until he dumped his mission's entire budget of $84,000 on the desk of Assistant Director D.M. Ladd. At this point he was taken seriously and interrogated for hours. None of the others knew of the betrayal. Over the next two weeks, Burger and the other six were arrested. All eight were put on trial before a seven-member military tribunal on specific instructions from President Franklin D. Roosevelt. They were charged with 1) violating the law of war; 2) violating Article 81 of the Articles of War, defining the offense of corresponding with or giving intelligence to the enemy; 3) violating Article 82 of the Articles of War, defining the offense of spying; and 4) conspiracy to commit the offenses alleged in the first three charges.
Lawyers for the accused, who included Lauson Stone and Kenneth Royall, attempted to have the case tried in a civilian court but were rebuffed by the Supreme Court of the United States in Ex parte Quirin. The trial was held in the Department of Justice building in Washington. All eight defendants were found guilty and sentenced to death. Roosevelt commuted Burger's sentence to life and Dasch's to 30 years, because they had turned themselves in and provided information about the others. The others were executed on 8 August 1942 in the electric chair on the third floor of the District of Columbia jail and buried in a potter's field called Blue Plains in the Anacostia area of Washington. In 1948, President Harry S. Truman granted executive clemency to Dasch and Burger on the condition that they be deported to the American Zone of occupied Germany.