When Annie and her brother Cory are orphaned Hettie's mother takes them in. Hettie and Annie sell watercress on the streets of Victorian London to make a living. Annie's dissatisfaction grows and her reckless ambition takes her on a separate path. After she disappears in mysterious circumstances Hettie sets out to find her. While searching for Annie, in the darkest and most dangerous part of London, she uncovers the corruption and depravity of Victorian society. Secrets are revealed that put both their lives put in danger. Can Hettie find her friend before it's too late?