Throughout 1942, German U-boats were sinking hundreds of American ships in the Atlantic Ocean, effectively cutting the supply line to embattled ally England. In desperation, the United States Navy turned to the National Cash Register Company in Dayton, Ohio, to design and build code-breaking machines. The high-priority and highly classified project involved hundreds of civilians, Naval officers and one engineer of German descent whose insight and technical ability helped break the complex Enigma code. Dayton Codebreakers uncovers Joseph Desch's role in helping end World War II, through interviews with eminent historians, scientists and honored war veterans. Although Desch remained faithful to his pledge of secrecy until his death in 1987, he left behind mysterious papers and clues for his daughter to unravel.

Sunday, 4/23 from 4:30-5:30 p.m. ET