In 1838, Benjamin January travels to Washington with Henri and Chloë Viellard to search for a missing friend. The disappearance leads into a world of political agents, slave catchers, coded messages and men whose public respectability conceals private violence.
January receives help from a young Edgar Allan Poe and encounters politicians including John Quincy Adams, but his own position remains dangerous in a city where free Black people can be abducted and sold. Solving the code reveals that the missing man’s fate is connected to a wider conspiracy whose participants are prepared to kill anyone who follows the trail.