Darkness can conceal identity and encourage moral transgressions; it may also induce a psychological feeling of illusory anonymity that disinhibits dishonest and self-interested behavior regardless of actual anonymity. Three experiments provided empirical evidence for this prediction. In Experiment 1, participants in a slightly dim room cheated more and thus earned more underserved money than those in a well-lit room. In experiment 2, participants wearing sunglasses behaved more selfishly than those wearing clear glasses. Finally, in Experiment 3, an illusory sense of anonymity mediated the relationship between darkness and self-interested behaviors. Across all three experiments, darkness had no bearing on actual anonymity, yet it still increased morally questionable behaviors. We suggest that the experience of darkness, even one as subtle as wearing a pair of sunglasses, may induce a sense of anonymity that is disproportionate from actual anonymity in a given situation.