A Eurocentric history mainly focusing on why evil exists and how philosophers such as Plato, Plotinus, Augustine, and others up through Kant and the 19th century Germans, delt with the metaphysical implications of its existence. There's no mention of more recent philosophers.
Most of the essays are quite good, and repetition between differently authored chapters is kept to a minimum. Between the philosophical works, there are pieces called "Reflections," which give shorter meditations on various aspects of evil in literature and society. It's a shame that Buddhist and other non-European viewpoints were not included as much of the metaphysics is grounded in Judeo-Christian theodicy.
Given the course of recent history, it's ironic to read Gabriel Motzkin on "Evil After the Holocaust," which never mentions Zionism while at the same time perfectly describing the malignant evil of Israel's genocide based on dehumanizing the indigenous population.