Moffat the Magniloquent returns. Events at Gibbous House are over a decade in the past. Penniless, he heads south to St Louis. On murdering one Anson Northrup, Moffat assumes his identity and becomes involved with an Underground Railroad scheme to free slaves and rob the New Orleans Mint. Moffat meets another cast of grotesques and occasional real-life characters, including Marie Laveau, when he gets to New Orleans.

The scheme is complex and involves two riverboats and hiding both the silver and slaves from the authorities and a traitor in the ranks. Moffat learns more of the truth behind his origins, his past and what happened at Gibbous House. Moffat encounters the redoubtable and attractive Miss Pardoner – a woman seemingly unaffected by the passage of time – once again.