Conspiracy is a thread that runs throughout the tapestry of Roman history. From the earliest days of the Republic to the waning of the Empire, conspiracies and intrigues created shadow worlds that undermined the openness of Rome’s representational government. To expose these dark corners and restore a sense of order and safety, Roman historians frequently wrote about famous conspiracies and about how their secret plots were detected and the perpetrators punished. These accounts reassured readers that the conspiracy was a rare exception that would not happen again—if everyone remained vigilant. In this first book-length treatment of conspiracy in Roman history, Victoria Pagán examines the narrative strategies that five prominent historians used to disclose events that had been deliberately shrouded in secrecy and silence. She compares how Sallust, Livy, and Tacitus constructed their accounts of the betrayed Catilinarian, Bacchanalian, and Pisonian conspiracies. Her analysis reveals how a historical account of a secret event depends upon the transmittal of sensitive information from a private setting to the public sphere—and why women and slaves often proved to be ideal transmitters of secrets. Pagán then turns to Josephus’s and Appian’s accounts of the assassinations of Caligula and Julius Caesar to explore how the two historians maintained suspense throughout their narratives, despite readers’ prior knowledge of the outcomes.