In 1943, a German factory worker named Otto Hampel and his wife, Elise, were found guilty of treason and sedition after writing anti-Hitler slogans on postcards and secretly distributing them around Berlin. It was an ingenious campaign of silent revolt for which the Hampels were ultimately executed by guillotine, though their brave legacy survived in the files of the Gestapo and was subsequently enshrined in Hans Fallada’s 1947 novel, “Every Man Dies Alone” .