The book goes a long way toward explaining the central enigma surrounding Ratzinger: How did this erstwhile liberal end up as the chief architect of the third great wave of repression in Catholic theology in the twentieth century?

Based on extensive interviews with Ratzinger's students and colleagues, as well as research in archives in both Bavaria and the United States, Allen's account showsthat Ratzinger's deep suspicion of "the world", his preoccupation with human sinfulness, and his demand for rock-solid loyalty to the church run deep. They reach into his childhood "in the shadow of the Nazis" and reflect his formative theological influences: Augustine, Bonaventure, and Martin Luther(!) rather than the world-affirming Thomas Aquinas.

When the cardinals of the Catholic Church next gather in the Sistine Chapel to elect a pope, Allen argues, they will in effect be deciding whether to continue the policies Ratzinger has been the central force in shaping.