Twins Seren and Osei — a Black woman and man raised separately by rival shadow courts after being found abandoned on the war-border at birth — are unknowingly used in the same political gambit: married off to the heirs of their respective enemy courts to forge a false peace. When the twins discover each other, and discover the truth of their origins, the marriages they are each fighting to escape become the only thing keeping their birth-world from being erased entirely.