When recently investigating a mystery rooted in Victorian London's fascination with the dead, Eliza Scarlet had discovered her own recently deceased father's lost casebook. With Henry Scarlet's book throwing up some puzzling questions, Eliza looks more closely into how he died. Was it really natural causes as was determined at the time? The final entry in the casebook takes Eliza to an abandoned prison on the outskirts of London. She and Duke investigate what seems like an empty building, but they soon discover that it is the hideout for a criminal gang. But how is this gang linked to Henry Scarlet? With her resolve to solve this most personal of cases growing, is Eliza really ready for the terrible secret that is about to be uncovered?