With the enthusiastic assassins Croup and Vandemar on her trail, Door returns to her family home and finds her father's dying secret--one that could lead her to her true enemy, who has yet to reveal himself. In another part of London Below, Richard faces the terrifying Night's Bridge.

Richard is saved from being killed by the Rat-speakers when one of their masters, the rat who delivered a message from de Carabas to Door, recognizes him. Door returns to the home of her slain family with the Marquis and uncovers Vandemar and Croup as their killers, but who hired the two assassins remains a mystery. Vandemar and Croup, meanwhile, intimidate Varney into going to the floating market to secure a position as Door's bodyguard with the intention of betraying her to them later. Richard also remembers that Door is headed to the market. The Rat-speaker Anesthesia agrees to show him the way, but they'll have to cross the Night's Bridge to get there.