Rome, 44 BC. Julius Caesar has become dictator for life and is preparing to leave for war against Parthia, but rumours of conspiracy are spreading through the city. Gordianus has retired from investigation, yet Caesar and Cicero both draw him back into public danger by asking him to listen for threats against Caesar’s life. The novel follows the days before the Ides of March, using Gordianus’s inquiries to move among senators, loyalists and possible assassins as the Republic approaches its most famous political murder.