When Aria and Liam arrive in ancient Rome, they learn of a plot to assassinate Julius Caesar. They know what comes next: Caesar's death will lead to the fall of the Roman Republic. If they want to change history, they have to keep him alive.
With help from their new allies, Gaia and Titus, they set out to find the culprit. But Rome is caught in a struggle for power, with rival politicians, shifting alliances, and so many schemes that Aria and Liam no longer know which one poses the real threat. Even Aria, who knows Roman history by heart, discovers that surviving it is very different from reading about it.
Then the four friends are separated, leaving Aria and Liam fighting to stay alive when they should be searching for Caesar's enemies. Time is running out, the assassination plot is moving forward, and they are no closer to discovering who is behind it. If they fail, they won't just lose Caesar and the Republic. Aria and Liam will be trapped in a Rome ruled by a ruthless leader, with no way back to their own time. Can they find the real conspirators, save Caesar, and rewrite history before Rome's future becomes their own?