Alongside a sophisticated mystery plot, Turton uses his novel to make a compelling philosophical argument about the possibility of redemption and moral growth. Blackheath is a type of futuristic prison wherein “by locking prisoners inside the murder, we give them a chance to atone for their own crimes by solving somebody else’s. It’s as much a service as a punishment” (381). Thus, Blackheath is explicitly set up to facilitate rehabilitation and redemption, at least on the surface. However, as Aiden comes closer to helping Anna meet the conditions of her release, the Plague Doctor warns that “my superiors do not want to see Annabelle Caulker leave Blackheath […] they’ll be looking for any excuse to keep her imprisoned” (389). Silver Tear later presents exactly this point of view when she blames the Plague Doctor for “open[ing] the door to a creature who must never be allowed to leave this house” (365). Silver Tear and her superiors represent the viewpoint that Anna will never be redeemed, while the Plague Doctor is hesitant and unsure of what to believe.

Aiden, on the other hand, is fully invested in the possibility of redemption, even though he is the individual who could most justifiably hate Anna.