After Susan declines to give pregnant Lucy Eames her job back in the brothel, Lucy is found wandering,blood-stained and dazed. In a nearby tenement,due for demolition to make way for the rail-road,a rent collector and Lucy's mother are found dead but Lucy has no recollection of events and Reid brings in progressive psychiatrist Dr Crabbe to try and help her remember being in the house. Reid discovers that Susan was instrumental in helping Lucy,making her a suspect,though she also informs him of Lucy's medical condition,which made her stay at the brothel impossible. However the detectives' investigations turn up the name of one other who would definitely benefit by the death of one of the victims.
—don @ minifie-1