The story begins with a discussion among Vandal leaders aboard a war galley. Hunegais, a moody and pessimistic Vandal, expresses his discontent with their empire, dismissing it as nothing more than a facade. He complains about their precarious position in Africa, having merely taken over the roles of Roman landholders without truly integrating with the native population. Athaulf, another leader, suggests that religious conversion might ease tensions with the orthodox locals, but Hunegais vehemently rejects the idea.

Genseric, the Vandal king, listens to this conversation with amusement. He is a strategic mastermind who has transformed the Vandals from land-based warriors into formidable sea raiders. Genseric reflects on his past achievements, including his alliances and battles against the Romans and other barbarian tribes, which have solidified his power.

As the leaders continue their discussion, Hunegais expresses satisfaction at their impending raid on Rome, while Athaulf points out Rome's resilience despite its apparent decline. The conversation shifts to historical figures, drawing parallels between their current situation and the past conflicts between Carthage and Rome.

The scene then shifts to Genseric's cabin, where he is approached by a mysterious stranger who claims to have been aboard the ship since it left Carthage. The stranger, who exudes an aura of ancient authority, warns Genseric of a traitor among his trusted companions and offers proof of this betrayal. He urges Genseric to exact vengeance on Rome, hinting at deeper, historical motivations.

Genseric, intrigued and disturbed by the encounter, follows the stranger's advice and discovers Athaulf dead in his cabin, with evidence of his treachery laid out before him. Athaulf had been plotting with the Romans to betray Genseric, and the stranger's intervention has revealed this plot in time. The story concludes with Genseric recognizing the coin left by the stranger, bearing the likeness of Hannibal, the legendary Carthaginian general. This revelation cements Genseric's resolve to destroy Rome, driven by a sense of historical vengeance.