Aachen Code, #1

During World War II, the United States decided to send 100 thousand soldiers to Aachen. This led to the release operation "E.21". Where a group of men had to decrypt Nazi messages. They had a short time to know what the Nazis were preparing before American soldiers broke into Aachen. Things turned to an unexpected tunnel when a woman joined them and discovered hidden secrets. What decision could the woman of a dead soldier and a mother of a daughter make to help her country win the war?