Retrospective Narrative
Since Chains is the first book in a continuing series, it's difficult to tell what distance Isabel, as our narrator, is telling the story from. We do know from the use of past tense in the narration, though, that she's speaking of events that have already taken place. The comfort in this is that we assume she survives the whole ordeal since, you know, she's the one telling it to us (unless she died and became a zombie, but we don't think it's that kind of book). Importantly, this also means that reading Chains feels like reading an actual account of a slave's life during the war.
Looking back on her initial journey to Curzon as a spy, Isabel says:
I thought it would be easy. I would run straight to the shed behind Bellingham's house, tap on Curzon's window, tell him the news, and hurry home. (10.27)
Obviously, she eventually found out that taking a major anti-Loyalist bombshell to one of the most powerful officials in the city wasn't a walk in the park. A more heartbreaking example of Isabel's retrospection occurs the night Madam orders Becky to give her cookies and the sweetmilk drink. Not knowing that Madam plans to sell Ruth that night, Isabel says that she "shall never forgive [herself]" for not seeing through Madam's kindness. Tear.