The Last Stoic is a story about appetite and fear, both modern and ancient. Half of the story's narrative occurs in the time and place of the ancient Roman Empire; the other half occurs in the present-day United States. A central conceit of the novel is that the parallels between the two eras are so strong that the narrative can continue uninterrupted as the setting shifts from historic Rome to modern America, alternating from chapter to chapter.

Marcus, a young man from a northern provincial border town, journeys deep into the heart of the empire and witnesses first-hand the excesses that can lead to ruin, both personal and political. His story offers an ancient commentary on the preoccupations of our own turbulent times.

Shortly after his arrival, the empire is thrown into a panic by an unprecedented barbarian attack on the capital. Suspicion and paranoia abound. A young Roman/American runaway named Patrick, disillusioned with his own life and the state of his country, becomes convinced that Marcus is a dangerous traitor. Culminating in a public accusation made by Patrick, Marcus is wrongfully imprisoned, exiled and tortured as an enemy of the state. In prison, he confronts the many contradictions he has found in his adopted home, and in himself.

Throughout the story, in both eras, the writings of the philosopher-emperor Marcus Aurelius (The Meditations) insinuate themselves unexpectedly into Marcus' life. In prison, he is saved by a chance meeting with Sextus Condianus, the "last Stoic" of the title, a cell-mate who is able to fully recite Aurelius' words and impart their wisdom. Ultimately, it is this unanticipated and unbidden instruction that gives the young man the strength he requires to survive. It becomes evident that the words of the venerable Stoic emperor have as much relevance to our own era as they did to his.