Sholom Schwartzbard killed Simon Petlura in an act of revenge. He admitted his crime and a French jury acquitted him in 1927. For Hannah Arendt, Schwartzbard's actions show that revenge can, in certain circumstances, be in the service of justice. This paper explores Hannah Arendt's distinction between reconciliation and revenge and argues that Hannah Arendt embraces revenge as one way in which politics and justice can happen in the world, but only under certain conditions. First, Arendt only endorses revenge when the crime calling forth vengeance is extraordinary, one that bursts the bounds of traditional legality. Second, the avenger must give himself up for judgment to the legal system, asking a jury to judge whether his extraordinary act was just even though it was illegal. These are strict conditions and will only rarely be met. When they are, revenge can be a profoundly political act in the service of justice, one that can restore a broken political order.