Despite the threat of summary trial and execution, a tiny minority of Germans opposed National Socialism by distributing dissident literature, meeting secretly to discuss politics and sheltering Communist Jews and other political outlaws. Gill documents such acts of courage along with the organized German resistance to Hitler, which, as he shows, had networks in the army, the church, the Abwehr (military intelligence and counterespionage agency), the Foreign Office and the conservative opposition. He profiles many unsung resisters along with such better-known heroes as outspoken Evangelical pastor Dietrich Bonhoeffer, hanged in a concentration camp; Col. Claus von Stauffenberg, shot for his key role in the 1944 plot to assassinate Hitler; and Hans and Sophie Scholl, the brother and sister who led the White Rose student anti-Nazi group, both beheaded in 1943. British historian Gill's illuminating study cogently argues that Hitler was not an irresistible force and that he succeeded only because he was allowed to.