Mushikiwabo is a Rwandan working as a translator in Washington when she learns that most of her family back home has been killed in a conspiracy meticulously planned by the state. First comes shock, then aftershock, three months of it, during which her worst fears are confirmed: The same state apparatus has duped millions of Rwandans into butchering nearly a million of their neighbors. Years earlier, her brother Lando wrote her a letter she never...