Other prisoners overhear the knocks. Some learn Günther’s knock language. Some develop their own. They knock to pass on information about their interrogations. They knock to warn about prison guards and stool pigeons. They knock to share news about the world, report battles won and lost. They knock to defy their captors, tell a joke, make a friend, pick a fight, howl their anguish. They knock to hear another human being knock. Late at night, a symphony of knocks can be heard.
