I assume that we find it hard to understand, for example, how a person could harm another person in cold blood. I then set out Kant's reason's for thinking that, strictly speaking, evil behavior is impossible: people may act on wicked desires but deliberate wrong-doing is not a genuine phenomenon. However, Kant's view is at odds with our common sense intuitions about morally evil behavior, namely, that such behavior is possible, albeit difficult to understand. I then suggest how Kant's analysis of the problem of evil behavior can help us to understand under what conditions evil behavior would be possible. Next, I introduce Peck's theory of how evil behavior can manifest itselfwhen a person suffers from malignant narcissism—a complaint that involves acting on principles which are not consciously acknowledged. I conclude that Kant's views on evil can be understood with reference to Peck's theory (and vice versa).