They left secret signs to show those who followed where one was welcome and where not. And they used a secret code to survive on the streets. They were called vagabonds, outcasts, itinerant people. Their enigmatic language, Rotwelsch, fascinated Martin Puchner as a child in the Franconian provinces back in the 1970s. Much later, as a professor at Harvard, he will research this code as a scientist - and realize that his own family is also ominously connected to this language. A moving and touching book about the uncanny power of words - and a dark family secret.